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A Kitchen Science Savant Shares His Secrets In 'The Food Lab'

Kenji Lopez-Alt is managing culinary director of Serious Eats, author of the James Beard Award-nominated column "The Food Lab," and a columnist for <em>Cooking Light.</em> His first book is <em>The Food Lab: Better Home Cooking Through Science.</em>
Robin Lubbock/WBUR
Kenji Lopez-Alt is managing culinary director of Serious Eats, author of the James Beard Award-nominated column "The Food Lab," and a columnist for Cooking Light. His first book is The Food Lab: Better Home Cooking Through Science.

Chef and food writer Kenji Lopez-Alt recently paid a visit to old stomping grounds: the Boston area, home to his alma mater, MIT.

He helped prepare one dinner at Roxy's Grilled Cheese, a small, hip sandwich shop in the Allston neighborhood, to share a recipe from his new book The Food Lab: Better Home Cooking Through Science.

The dinner featured a double-brined, Korean-inspired fried chicken sandwich. The Roxy cooks spent three days making it, closely following Lopez-Alt's methods for maximizing surface area in the breading and maintaining moisture in the chicken.

The techniques for the recipe can be traced back to Lopez-Alt's love of science. As he writes in The Food Lab, "My grandfather was an organic chemist. My father was a microbiologist and I was a little nerdling." At MIT, Lopez-Alt started off in biology, later switched to architecture, and began working as a chef for the first time at a Mongolian barbecue restaurant.

It was there that he realized how much he loved cooking. "There was a lightbulb moment as soon as I walked in the kitchen and started working," he tells Here & Now. "I love the physical action. I love the whole idea of feeding people and bringing people together over food. I love the craft involved."

But Lopez-Alt had some unanswered questions. Like, "Why do my pancakes taste so bad?" or "Does searing meat really lock the juices in?" After cooking professionally for eight years, Lopez-Alt left the chef's life and began to answer these questions through scientific experimentation as a test cook and editor for Cook's Illustrated and later as a columnist for

In his column on, called "The Food Lab," he divulges the detailed findings from these experiments. Here's one you can try at home. Take two identical steaks (or two groups of steaks, if you want some statistical heft) and sear one the traditional way: on a hot pan and then in an oven to finish. Cook the other steak in the oven and then finish it off with a sear. Try them side by side, take their mass, and see which is juicier. Spoiler: Searing after cooking gives you a juicier steak.

Why? Lopez-Alt says it's because searing an already-done steak takes less energy than searing a raw steak. The cooked steak is already hot, and the exterior is already dry. So you don't have to add much more heat to get the steak to brown. That means less time on the pan and less water loss from the inside of the steak.

Other recipes explore the Maillard reaction, the chemical reaction that causes browning when amino acids, or the components of proteins, react with sugars. It happens faster with a slightly higher pH, says Lopez-Alt. You can raise the alkalinity of pancake batter by adding more baking soda. That will give you browner, and better, pancakes, since that Maillard reaction is happening faster, he says.

All this science has led to some other seriously good recipes. In Boston, the double-brined, double-fried, Korean-inspired chicken sandwich was a hit. "It has sex appeal. Delicious," one diner said.

Lopez-Alt's Classic Diner-style Smashed Cheeseburgers.
/ Courtesy of Kenji Lopez-Alt
Courtesy of Kenji Lopez-Alt
Lopez-Alt's Classic Diner-style Smashed Cheeseburgers.

Recipe: Classic Diner-Style Smashed Cheeseburger from The Food Lab

Note: Lopez-Alt's toppings of choice are thinly sliced raw onions, pickles and fry sauce (recipe below), but feel free to use whatever you'd like.

Serves 2 to 4

1 pound freshly ground beef (store-bought or home-ground)
4 soft hamburger buns, preferably Martin's Potato Sandwich Rolls
2 tablespoons unsalted butter, melted
Vegetable oil
Kosher salt and freshly ground black pepper
1 small onion, finely sliced (optional)
4 deli-cut slices American cheese
Toppings as desired

  1. Divide the meat into 4 even portions and form into pucks about 2 inches high and 2 1/2 inches wide. Refrigerate until ready to use.
  2. Open the buns but do not split the hinges. Brush lightly with the butter, then toast under a hot broiler or in toaster oven until golden brown, about 1 minute. Set aside.
  3. Using a wadded-up paper towel, rub the inside of a 12-inch heavy-bottomed stainless steel or cast-iron skillet with vegetable oil, then heat over medium-high heat until just beginning to smoke. Season the beef pucks on the top with salt and pepper, then place seasoned side down in the skillet. Using a wide heavy spatula, press down on each one until it is roughly 4 to 4 1/2 inches in diameter and 1/2 inch thick; it helps to use a second spatula to apply pressure on the first one. Season the tops with salt and pepper. Cook, without moving the burgers, until a golden brown crust develops on the bottom, about 1 1/2 minutes. Use the edge of the spatula to carefully scrape up and flip the patties one at a time, making sure to get all the browned bits. If using onions, add to the tops of the burgers, then cover each with a cheese slice. Continue to cook until the patties are the desired doneness — about 30 seconds longer for medium-rare.
  4. Top the buns and/or patties as desired, transfer the patties to the buns, close the burgers, and serve.


Go to any burger joint in the Midwest and ask for fry sauce, and you'll get a little tub of pink, creamy goo to dip your fries in or slather on your burger. At its most basic, it's a mix of mayo and ketchup. I like to liven mine up with a few spices and some pickle juice.

Makes about 2/3 cup

1/2 cup mayonnaise, preferably homemade (page 807)
2 tablespoons ketchup
1 tablespoon yellow mustard
1 tablespoon kosher dill pickle juice
1 teaspoon sugar
Pinch of cayenne pepper

Combine all the ingredients in a bowl and whisk until smooth. The sauce will keep in a covered container in the fridge for up to 2 weeks.

Lopez-Alt's Ultra-gooey Stovetop Mac 'n' Cheese.
/ Courtesy of Kenji Lopez-Alt
Courtesy of Kenji Lopez-Alt
Lopez-Alt's Ultra-gooey Stovetop Mac 'n' Cheese.

Ultra-Gooey Stovetop Mac 'N' Cheese

If desired, top the mac with toasted bread crumbs just before serving.

Notes: Use a good melting cheese or combination thereof, like American, cheddar, Jack, Fontina, young Swiss, Gruyere, Muenster, young provolone, and/or young Gouda, among others (see "Cheese Chart," pages 717–21). To reheat the pasta, add a few tablespoons of milk to the pan and cook, stirring gently, over medium-low heat until hot.

Serves 4 to 6

1 pound elbow macaroni
Kosher salt
One 12-ounce can evaporated milk
2 large eggs
1 teaspoon Frank's RedHot or other hot sauce
1 teaspoon ground mustard
1 pound extra-sharp cheddar cheese, grated (see Note above)
8 ounces American cheese, cut into 1/2-inch cubes (see Note above)
1 tablespoon cornstarch
8 tablespoons (1 stick) unsalted butter, cut into 4 chunks

  1. Place the macaroni in a large saucepan and cover it with water by 2 inches. Add a pinch of salt and bring to a boil over high heat, stirring occasionally to keep the pasta from sticking. Cover the pan, remove from the heat, and let stand until the pasta is barely al dente, about 8 minutes.
  2. Meanwhile, whisk together the evaporated milk, eggs, hot sauce, and mustard in a bowl until homogeneous. Toss the cheeses with the cornstarch in a large bowl until thoroughly combined.
  3. When the pasta is cooked, drain it and return it to the saucepan. Place over low heat, add the butter, and stir until melted. Add the milk mixture and cheese mixture and cook, stirring constantly, until the cheese is completely melted and the mixture is hot and creamy. Season to taste with salt and more hot sauce. Serve immediately, topping with toasted bread crumbs if desired.


Stir in 1 cup cubed sauteed ham and 1 cup thawed frozen peas along with the milk and cheese mixtures in step 3.


Slice 6 strips bacon into 1/2-inch-wide pieces, place in a large skillet with 1/2 cup of water, and cook over medium heat, stirring occasionally, until crisp. Transfer the bacon and its rendered fat to a small bowl and set aside.

Follow the instructions for Stovetop Mac 'n' Cheese, reducing the butter to 6 tablespoons and stirring in the bacon, with its rendered fat, and 1/4 cup sliced pickled jalapeños along with the milk and cheese mixtures in step 3.


Stir in 1 cup blanched broccoli florets and 1 cup blanched cauliflower florets along with the milk and cheese mixtures in step 3.


Replace half of the cheddar cheese with mozzarella. Stir in 1 ounce of Parmesan cheese grated, 8 ounces Italian sausage, cooked and crumbled, 1/4 cup pepperoni cut into 1/2-inch chunks, 4 ounces soppressata or salami, cut into 1/2-inch chunks, 1 cup roughly chopped drained canned tomatoes, 1/4 cup sliced pitted black olives, and 1/4 cup sliced jarred peperoncini, into the finished mac 'n' cheese. Top with chopped basil and drizzle of extra-virgin olive oil.


Replace the cheddar cheese with pepper Jack. Stir in 2 cups shredded cooked chicken (leftover or rotisserie from the supermarket), one 3 1/2-ounce can chopped green chilies (or 1/2 cup chopped roasted fresh green chilies), and 1 cup salsa verde into the finished mac 'n' cheese. Sprinkle with chopped fresh cilantro and scallions.

Lopez-Alt's Extra-crunchy Southern Fried Chicken.
/ Courtesy of Kenji Lopez-Alt
Courtesy of Kenji Lopez-Alt
Lopez-Alt's Extra-crunchy Southern Fried Chicken.

Extra-Crunchy Southern Fried Chicken

Serves 4

2 tablespoons paprika
2 tablespoons freshly ground black pepper
2 teaspoons garlic powder
2 teaspoons dried oregano
1/2 teaspoon cayenne pepper
1 cup buttermilk
1 large egg
Kosher salt
One whole chicken, about 4 pounds, cut into 10 pieces (see "How to Break Down a Chicken," page 363) or 3 1/2 pounds bone-in, skin-on breasts, legs, drumsticks, and/or wings
1 1/2 cups all-purpose flour
1/2 cup cornstarch
1 teaspoon baking powder
4 cups vegetable shortening or peanut oil

  1. Combine the paprika, black pepper, garlic powder, oregano, and cayenne in a small bowl and mix thoroughly with a fork.
  2. Whisk the buttermilk, egg, 1 tablespoon salt, and 2 tablespoons of the spice mixture in a large bowl. Add the chicken pieces and toss and turn to coat. Transfer the contents of the bowl to a gallon-sized zipper-lock freezer bag and refrigerate for at least 4 hours, and up to overnight, flipping the bag occasionally to redistribute the contents and coat the chicken evenly.
  3. Whisk together the flour, cornstarch, baking powder, 2 teaspoons salt, and the remaining spice mixture in a large bowl. Add 3 tablespoons of the marinade from the zipper-lock bag and work it into the flour with your fingertips. Remove one piece of chicken from the bag, allowing excess buttermilk to drip off, drop the chicken into the flour mixture, and toss to coat. Continue adding chicken pieces to the flour mixture one at a time until they are all in the bowl. Toss the chicken until every piece is thoroughly coated, pressing with your hands to get the flour to adhere in a thick layer.
  4. Adjust an oven rack to the middle position and preheat the oven to 350 F. Heat the shortening or oil to 425 F in a 12-inch straight-sided cast-iron chicken fryer or a large wok over medium-high heat. Adjust the heat as necessary to maintain the temperature, being careful not to let the fat get any hotter.
  5. One piece at a time, transfer the coated chicken to a fine-mesh strainer and shake to remove excess flour. Transfer to a wire rack set on a rimmed baking sheet. Once all the chicken pieces are coated, place skin side down in the pan. The temperature should drop to 300; adjust the heat to maintain the temperature at 300 for the duration of the cooking. Fry the chicken until it's a deep golden brown on the first side, about 6 minutes; do not move the chicken or start checking for doneness until it has fried for at least 3 minutes, or you may knock off the coating. Carefully flip the chicken pieces with tongs and cook until the second side is golden brown, about 4 minutes longer.
  6. Transfer the chicken to a clean wire rack set on a rimmed baking sheet and place in the oven. Cook until an instant-read thermometer inserted into the thickest part of the breast registers 150 F and the legs register 165, 5 to 10 minutes; remove the chicken pieces to a second rack or a paper-towel-lined plate as they reach their final temperature. Season with salt and serve — or, for extra-crunchy fried chicken, go to step 7.
  7. Place the plate of cooked chicken in the refrigerator for at least 1 hour, and up to overnight. When ready to serve, reheat the oil to 400 F. Add the chicken pieces and cook, flipping them once halfway through cooking, until completely crisp, about 5 minutes. Transfer to a wire rack set on a rimmed baking sheet to drain, then serve immediately

Recipes reprinted from The Food Lab by Kenji Lopez-Alt. Copyright © 2015 by Kenji Lopez-Alt. With permission of the publisher, W. W. Norton & Co. Inc. All rights reserved.

This interview originally aired on Here & Now, a public radio show from NPR and WBUR in Boston.

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