-today on "america's test kitchen," julia and bridget make sensational beef stir-fry, jack challenges bridget to a tasting of soy sauce, and keith makes julia unforgettable scallion pancakes. it's all coming up right here on "america's test kitchen." "america's test kitchen" is brought to you by the following -- fisher & paykel. since 1934, fisher & paykel has been designing

a wide range of kitchen appliances, including built-in ovens, cooktops, ranges, refrigerators, and dishdrawer dishwashers. our passion is turning everyday cooking experiences into culinary creations. cook to create. learn more at fisherpaykel.com -quinoa, chia, flaxseed, farro, whole-wheat flour, coconut flour, almond meal, steel-cut oats, muesli, 10-grain cereal, wheat germ, oat bran, millet, tapioca flour... -"america's test kitchen" is proudly sponsored by kohler. we design innovative sinks and faucets for people who do their best work in the kitchen. ♪ -and by siematic -- the art of kitchen interior design

inspired by your lifestyle. siematic. -holland america line sails to over 400 ports of call, transporting guests to the world's wonders. information available through a travel professional or at hollandamerica.com. blue apron. ♪ -the worst part of beef stir-fry -- well, it's the beef. -yep. it's usually overcooked, rubbery, and gray. -but today, we're going to fix that once and for all. -that's right. and it starts by using the right cut of beef, and here we have a flank steak. and we like flank steak because it's an inexpensive cut of meat, has a big, beefy flavor, and it's easy to cut into bite-size pieces, which is what you want for a stir-fry. now, cutting the flank steak in the right direction means everything. first, i'm gonna cut it with the grain into just smallish pieces, about 2 to 2 1/2 inches wide. and then, taking one of these pieces at a time, i'm gonna cut it crosswise,

against the grain, into about 1/4-inch-thick slices. all right, so, that was a pound of flank steak. you know when you go out to a chinese restaurant how the beef always tastes really tender and supple? -yes. -that's because they use a technique called "velveting," where you take the beef, you let it sit in a mixture of egg whites and cornstarch and some seasonings for about 30 minutes. now, it's a good technique. we tried it here in the test kitchen, but it's a real mess. you don't want to mess with it at home, so we found a simpler way -- using baking soda, because baking soda, much like the egg whites, tenderized the meat. so, this is 1/2 teaspoon of baking soda. we're gonna mix that with a tablespoon of water. now we're gonna add the beef, toss it all together, and let it sit for about five minutes. -and that's hardly any of that mixture in there. you don't need a lot. -you don't need a lot. -so, how does adding baking soda to the meat help tenderize it? well, the baking soda raises the meat's ph, which alters the electrical charges on the proteins. like electrical charges repel, so when we increase the ph of the meat,

we create more negative charges, and that forces the proteins apart. when the proteins move farther apart, they become easier to bite through, and, therefore, the meat is more tender. -all right, so, while that meat sits there and gets tender, we're gonna start prepping the vegetables. and we're gonna use two bell peppers -- different colors 'cause it looks pretty. and the easy way to cut up a bell pepper for stir-fry is, first, lop off the top and the bottom, then slice down through the pepper right through the side. and then we're gonna open it up, cut away the core and any of those ribs. and now you have a nice, flat piece of pepper that you can just slice. and we're gonna cut it into 1/4-inch-thick slices. -it's always a good idea to prep all of your vegetables, your meat -- everything -- ahead of cooking with stir-fry, 'cause once you start cooking, it goes very, very fast. -so, the peppers are done, and on to our second vegetable -- scallions. now, we're gonna treat the whites like an aromatic and sauté it later with the garlic and ginger, but we're gonna treat the greens like a vegetable. so, in order to prep scallions,

you first just want to trim off the ends, and then we're gonna slice this scallion in half, right where the dark green starts to turn into light green. so, i'm gonna cut this into about 3-inch lengths, and then we're gonna add it to the bowl of vegetables. and then i'm just gonna slice the scallion white on the bias into nice, thin slices. six scallions altogether. gonna put these in a separate bowl. so, it's time to make the sauce. and we're gonna make a spicy, peppery, cantonese-style sauce, and it starts with a little water. this is 1/4 cup of water, and into it, we're gonna put 2 tablespoons of soy sauce, 2 tablespoons of dried sherry, and this is 1 tablespoon of oyster sauce. it really adds that deep, earthy flavor. next, we're gonna add 2 teaspoons of brown sugar. and here's the spicy bit -- 2 teaspoons of ground black pepper. 2 teaspoons of rice vinegar. just a teaspoon and a half of sesame oil. last but not least, the thickener.

this is a teaspoon and a half of cornstarch. and that's it. we're just gonna whisk this together, and our sauce is done. that beef has been sitting with the baking soda for five minutes, so it's good and tender. now it's time to give it a little flavor. so, using pretty much the same ingredients that were in the sauce, we're gonna start with a tablespoon of soy sauce. to that, we're gonna add a tablespoon of sherry, a little bit of cornstarch. and, again, that cornstarch is gonna help protect the meat as it cooks, so it stays nice and tender. so, this is a teaspoon and a half of cornstarch. last but not least, 1/2 a teaspoon of brown sugar helps the meat brown as we cook it. i'm just gonna mix this together to dissolve the cornstarch and the sugar, and now we're gonna just pour it over the beef. it's easy as that. all right, so, everything's prepped. we have the beef, the vegetables, and the sauce, and that meat has been sitting for at least 15 minutes, so it's soaked up some of that flavor. it's time to get cooking. into this nonstick skillet, i'm gonna put 2 teaspoons of vegetable oil. i'm gonna heat it up over high heat till it's just smoking.

so, to make stir-fry, we never use a wok. we always use a flat, nonstick skillet because the flat surface makes better contact with our flat stoves, so it gets more even heat. all right, so, we're just gonna add half the meat so that each piece can get a nice, good sear. and then i'm gonna quickly spread it out into an even layer, and then we're just gonna let it cook undisturbed for about one minute and get some good browning on each piece of meat. all right, so, it's been about a minute, so it's time to give it a good stir. put it brown side up, let it go for about another minute. these guys are good and browned on both sides, so it's time to take them out of the pan. back on the stove. 2 more teaspoons of oil, and we'll do that second batch of beef. ooh, look at that second side -- nice and brown. so, out of the pan goes our second batch of beef. time to cook the vegetables. and for the vegetables, we're gonna add another 2 teaspoons of vegetable oil.

we're gonna add all the peppers and the scallion greens. so, it's been about four minutes, and you can see they have a nice spotty brown. they're not completely tender. they're just crisp tender. little bite left in them. so, i'm gonna add them to the bowl with the beef. back on the stove. now, i'm gonna turn the heat down to medium high, and we're gonna sauté the aromatics. so, i'm gonna add 4 teaspoons of oil. now we're gonna add those scallion whites that i kept separate, along with a tablespoon of freshly minced ginger and three cloves of minced garlic. so, this is gonna cook for about two minutes, until those scallions have softened. starting to get a little brown, and those scallions are soft, so now it's time to add everything back to the skillet. so, here, we're gonna add both batches of beef and all the vegetables, along with any accumulated juices. all right, and we're gonna give it a little toss. ohh! -so good. -doesn't that look good? now, last but not least, is our sauce. now we're gonna add it to our nice, hot skillet.

-mmm. -and it's gonna come to a simmer, and as it simmers, that cornstarch is gonna thicken. [ both chuckle ] oh, doesn't that look good? -we're about eight blocks past good, julia. [ both laugh ] -we are all done cooking. -yeah. -now, that is a stir-fry, my friend. i'm gonna put a little rice in the bottom of our bowls. now for the beef stir-fry. -mmm. -beautiful. -mmm. -mm-hmm. -i never in my life thought i would say "flank steak" and "melt in your mouth" in the same sentence. -right? -it's so tender. the bell peppers cooked absolutely perfectly. -mm-hmm. -still a little bit crisp... -yeah. -...but tender. i love every single thing about this, except for the bowl is too small. -mm-hmm. -our beef stir-fry with bell peppers and black-pepper sauce really delivers, and the key is creating tender beef. cut flank steak across the grain into bite-size pieces, soak the meat in a mild baking-soda solution, and add cornstarch to the savory marinade.

flash-sear the steak in a very hot pan, followed by peppers and scallions, then finish with a savory sauce. so, there you have it, from the test kitchen to your kitchen -- the very best beef stir-fry with bell peppers and black-pepper sauce. ♪ soy sauce can be used in so many more things than just stir-fry sauces and marinades, and jack is here to tell us which sauce is best. -we use a lot of soy sauce here in the test kitchen. it goes into everything from our favorite chili to stews, all kinds of european dishes -- not just asian dishes -- to add meaty, savory notes, 'cause it's got a lot of glutamates, and glutamates build big flavor. -sure. -so, before we taste, i want you to smell them, because you're gonna learn a lot from the aroma. so, we rounded up the 10 best-selling brands of soy sauce, made in china, the united states, and japan. we included tamari. it's got a lot of press now because it's gluten-free.

regular soy sauce is boiled soy beans along with roasted wheat that are fermented, much like you ferment bread or pickles, and it takes time to develop all those flavors. tamari, they leave out the wheat. now, what the wheat is doing is adding some sweetness to balance out the saltiness. so, what you're looking for is complexity -- obviously, saltiness and meatiness, but honeysuckle, melon, pineapple, strawberry, smoke. -things i would've never thought of in soy sauce. -the ones that are very metallic, musty, and sour, those are not good things. those are things that we really downgraded quite substantially in the taste test. we sample them the way you are sampling them here. we also cooked with them. the other big difference we found among the soy sauces is they can be done through a traditional fermentation process, and that will take anywhere from two months to two years. -mm-hmm. -and that really builds the flavor. all the top brands, that's how they're made. some of the lower-rated brands that are made here in the u.s., they're using a shortcut called hydrolysis,

and basically, they use hydrochloric acid to speed up the process, and it takes two days, rather than many months or many years, to make soy sauce. all at the bottom of the rankings. you want to avoid those brands. -well, they are all very well-seasoned. [ both laugh ] -yes, they are. -that is for sure. and some of them are very salt-forward. this one, in particular, when i taste it, it tastes... i almost get a...cognac? you know, that warm feeling that you get with a nice glass of cognac. it's that same kind of secondary flavor that i'm getting there. this particular one... it's got a taste, and i don't know if i like it or not. -okay. and the two on the ends? not sure if you're liking those or what your opinion is? -this tastes like liquid salt to me. -okay. the tasting panel found that some were just simply too salty, and it sounds like you think that one falls into that category. -definitely. there's something underneath here,

and i can't put my foot on it -- or my finger. i don't like that one. -and what don't you like? -there's something really sharp there. -so, it sounds like you have very definite opinions about what you like. -yes. this is 100% -- not crazy about this. between these two, i think this is my favorite. -do you want to start with what you liked? -yes. let's go with what i liked first. -so, you chose the most expensive one. [ both laugh ] this is also probably the most artisanal. it's a japanese brand. it is fermented for two years. it's about $10 for a little bottle of soy sauce. it was fourth place. we liked it. it's very delicate. for a dipping sauce, it's really a nice choice. at $10 for a bottle, i'm not sure i want to be making a marinade with it. -so, this one was my runner-up. -and you've really surprised me here. so, this is american-made, very familiar. la choy. -no! -this is the one that is hydrolyzed, so it is not really fermented. -you're kidding me! -so, it was in the middle of the pack, actually. -okay. people who were like, "this is totally familiar.

this is the soy sauce of my childhood." but for most americans, who didn't grow up in a family where they were using a lot of soy sauce, the soy sauce of our childhood is not necessarily a good thing, and so this was a brand where, really, i think it's kind of one-dimensional. -you're right. i mean, there is a little bit of the "to-go packets of soy sauce" thing going on there. maybe that's what i was connecting to. and then this one. -this was at the bottom of the rankings. this is one of the tamaris, and you said it was way too salty. the tasting panel said this is the problem with the tamaris. without any of the wheat, you don't get any of the sweetness to balance out all the saltiness, and they're just really, really one-dimensional and overpowering. -so, i'm guessing this is the winner. -the winner is kikkoman. it was the panel's favorite choice. made here in the u.s. it is fermented for six to eight months. it's not as delicate as the one that you liked, but it really has all those savory soy sauce notes that you want. -it sure does. i mean, it's very strong. so, maybe i just have a delicate palate. -or maybe you're not supposed to drink soy sauce out of a glass. [ both laugh ] -that could be true, yes. great advice. do not drink soy sauce out of a glass.

but if you'd like to try the winner, it's kikkoman soy sauce, and that's $2.79 a bottle. ♪ -i always order scallion pancakes whenever i go out for chinese food, and more often than not, i wind up with something like this guy. he's gross. he's soggy, he's super-greasy, he has no flavor, and he has no structure. but it wasn't until keith started churning out some seriously good versions right here in the test kitchen that it dawned on me that i can just make them myself. -i did the same thing for years, julia, but they're really simple to make, i've found out. it's just four ingredients -- flour, water, oil, and scallions. -that's it. -really simple. and when you make them at home, they can be so good. they're super-crisp and flaky on the outside, tender and chewy on the inside. so, we found that a cold-water dough was really hard to work with. it was super-sticky and it was really hard to roll out. boiling water made a supple dough that was really easy to work with. so, i have 1 1/2 cups of all-purpose flour in here,

and i'm gonna pour 3/4 of a cup of boiling water, and it's gonna create a shaggy dough. at a certain point, the spoon doesn't really work for me. it just kind of knocks the dough around, so i like to get my hand in there and work with it. we're gonna put this on the counter. then i'm just gonna knead this for three or four minutes, until it's smooth. now, we want to keep this dough nice and soft. it should feel kind of like play-doh. it's kind of going back to your childhood. -it kind of looks like play-doh. -so, this has been about four minutes. the dough is fairly smooth. it's not perfectly smooth. but we're just gonna kind of shape it into a ball here, and we're gonna let this rest for 30 minutes. the gluten's gonna relax, and that's gonna make rolling it out into a pancake a little bit easier. -let's talk about how that boiling water is the key to making this dough. flour is made up of starch and proteins. when we add boiling water directly to the flour, two things happen. one, starch granules absorb water and swell, leaving less water to make the protein sticky, and two, the hot water straightens out some of the coils in the gluten structure,

reducing the dough's tendency to snap back when you roll it out. -exactly. so, the dough is resting. now we're gonna make a quick dipping sauce. -all right. -i have five scallions here. so, really simple. you want to do a nice, thin slice. you don't have to get too fine here. so, we're gonna take about a tablespoon of these and we're gonna set that aside for our dipping sauce. we're gonna start with soy sauce. we have 2 tablespoons here. this is gonna give us a nice, deep, complex background. and then we have 1 tablespoon of water, 1 teaspoon of toasted sesame oil. that's gonna give it a nice, nutty background. and a healthy pinch of chili flakes. 2 teaspoons of rice-wine vinegar. we're also gonna add a teaspoon of honey to this, too. -that looks like a nice generic sauce that you could use for a lot of things, like dumplings. -exactly. exactly. so, our dough has rested for 30 minutes, and now it's time to make the pancakes. -let's do it. -i'm gonna slowly preheat our 10-inch cast-iron skillet. so, here we have our dough. and as it's sat for 30 minutes, it does get a little stickier, so i'm just gonna start with a little bit of bench flour here.

just gonna cut this in half. i'm gonna put the other half back in this bowl again, then cover it with our plastic wrap, just to keep it moist again so it doesn't dry out as we're doing this. we're gonna go for a 12-inch circle here. and if you're anything like me, you never end up with a perfect circle, but that's okay. -always a little of an amoeba shape. -exactly. but, you know, it doesn't make any difference here at all. now, you can see that the dough is really easy to roll out. it's not snapping back at all. okay, i'm just gonna check my work here. i think that's good. so, we've been talking about flakiness. and now we're getting to the part where we're gonna make that dough flaky. so, we have a tablespoon of all-purpose flour in here, and i'm gonna add a tablespoon of vegetable oil and a tablespoon of sesame oil. and that sesame oil is gonna give us that nice scallion-pancake flavor. and just a quick stir. now we have a nice, homogenous paste here. we're gonna measure a tablespoon of this out, and we're gonna drizzle it over this pancake, like that. like a croissant or a pie dough, you have a lean dough with fat in between it. when that fat melts, it creates steam,

and it separates those pieces. and what's gonna happen is, that flour in the paste is gonna absorb the oil, rather than the dough. -oh, so you're almost turning the oil into more of a solid state so it stays on the surface of the dough instead of getting absorbed. -exactly. -and you can see it's just sitting right on top of the dough. -and it will stay like that over time, too. we're just gonna use two scallions' worth. just kind of make a nice, even layer over here, like that. and we have a 1/2 teaspoon of kosher salt here, just for a little bit of flavor, little bit of texture. so, now, this is my favorite part here. we're gonna roll this up into a cylinder, and this is where we're gonna create our flaky texture. -you really are making it look like play-doh, a little bit. [ laughs ] -so, now that we have our cylinder, we're gonna roll it into a coil, like this, and we're gonna create even more layers. -it's a pinwheel of layers. -exactly. then, when we get to the end, we're just gonna take this tail and tuck it underneath, like that, and press it down. -that is cool. -okay. so, we have one.

we're just gonna keep this covered up with some plastic wrap to keep it moist. then i'm gonna start with our second one. we have our rolled and coiled doughs here, and we're gonna get ready to cook. i'm just gonna, again, use a little bit of bench flour here. i'm just gonna pick these up. this time, we're gonna roll it out into a 9-inch circle, and that's gonna fit perfectly into our 10-inch skillet that's preheating over there. okay, perfect. we have a 9-inch circle. now, one more step before we get to cooking, and that is cutting a little half-inch slit in the middle of our pancake. we were finding, when we put the pancake into the skillet, that steam that's being created by that hot oil was coming up and ballooning the pancake up. so what's gonna happen is, any steam that's created, it's gonna come through that slit. -very cool. -okay, so, our first one's done. we're gonna move on to our second one now. now it's time to cook. and we're gonna start with 2 tablespoons of vegetable oil. you want this pan hot, but you don't want it smoking-hot,

and you can see how the oil is shimmering like a spider web with just a few wisps of smoke. that's perfect. that's exactly what we want. so, we're just gonna take this pancake and we're gonna lay it in here like this. [ sizzling ] -ooh, a nice little sizzle. s-yeah, it should sizzle a little bit. i'm just gonna give it a little bit of shake, because that's also gonna allow that steam to kind of escape out. and now i'm gonna cover it, which is really kind of weird for something that's supposed to be crisp. -yeah. -but we found that sometimes the outside cooked through before the inside cooked, so we had this kind of raw, doughy interior. by covering it, we're kind of steaming the top and steaming the interior, so it's gonna be perfectly cooked by the time the outside is cooked. so, it's been a minute. before we flip it over, we're gonna add a little bit more oil to the pan, directly on top of the pancake. that's just to make sure that when we flip it over, that side is gonna have plenty of oil coating on it so it'll get browned again. -that makes sense. -grab it. -ooh, it smells good. -it does smell great. -ohhhh, hello!

-you always want to flip away from you, right, so if you have hot oil, you're not flipping it on top of you. so, we're just gonna cover it and let it go for another minute. i think our second side is brown. we'll just check it really quickly. almost there, but now it's time to take the cover off. we don't want to keep the cover on the whole time because we don't want to keep the crispy side steamed. -i was wondering. -exactly. so, what we're gonna do is, we're gonna let it brown another 30 to 60 seconds on this side, get it nice and golden brown. we're gonna flip it over to the second side and do the same thing. -okay. -so, this is ready to come up. it's crisp on both sides. we're just gonna put that over there on a wire rack. -this thing looks seriously hot. i can see oil bubbling in there. yeah, you want to give that a couple minutes before you eat it. so, we're gonna cook our second one now. we're just gonna put 2 tablespoons of oil in the pan -- same thing. so, our second pancake's ready, and it's time to eat. [ crunching ] -oh, you can hear the crunch. -doesn't it sound great? -well, test number 1 -- it doesn't flop over. -yeah, and so, you can see all these nice flaky layers

that we built in here, just like a croissant. and you have your dipping sauce. -mm-hmm. [ laughs ] mm-hmm. it amazes me that this was so easy to make and i've been ordering them all this time. -four simple ingredients -- that's it. crispy on the outside, has a nice, tender, chewy interior. it's perfect. -and it has good flavor. nice job, keith. these are awesome. -glad you like them. -so, if you really want terrific scallion pancakes, you're gonna have to make them yourself. start with a simple dough made of flour and boiling water and let it rest for 30 minutes before rolling it out. when shaping the pancakes, brush the dough with a paste made of oil and flour to get that flaky, super-crisp texture. finally, cook the pancakes in a cast-iron skillet to a deep, golden brown. and there you have it, from "america's test kitchen" to your kitchen -- an excellent recipe for scallion pancakes with dipping sauce. you can get this recipe, all the recipes from this season, along with our tastings, testings, and selected episodes on our website, americastestkitchen.com.

-let us help you with dinner tonight. visit our website anytime for free access to this season's recipes, taste tests, and equipment ratings, or to watch current-season episodes. log on to americastestkitchen.com. "the complete america's test kitchen tv show cookbook" includes every recipe, taste test, and equipment rating from all 17 years' shows. it's our most comprehensive collection ever. the cost is $19.95 -- 55% less than the cover price of $45. to order, call 1-800-888-3384 or order online at americastestkitchen.com. when you order, you can receive a 14-day trial membership to our new online cooking school at no cost. "america's test kitchen" is brought to you by the following -- fisher & paykel. since 1934, fisher & paykel has been designing a wide range of kitchen appliances, including built-in ovens,

cooktops, ranges, refrigerators, and dishdrawer dishwashers. our passion is turning everyday cooking experiences into culinary creations. cook to create. learn more at fisherpaykel.com. -honey oat granola, gluten-free pancake mix, gluten-free pizza crust mix. i'm bob moore, founder of bob's red mill, and that's me on every package. oh, extra-thick rolled oats, corn grits, cornmeal, lentils, buttermilk pancake mix. -"america's test kitchen" is proudly sponsored by kohler. we design innovative sinks and faucets for people who do their best work in the kitchen. ♪ -and by siematic -- the art of kitchen interior design inspired by your lifestyle. siematic.

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