The Burger Technique Alton Brown And In-N-Out Share

You are probably already primed to listen to any advice Alton Brown has for what to put on a burger, but when you know In-N-Out uses the same secret ingredient, it quickly becomes something essential. The all-American burger has been examined from so many angles at this point that you would think there just aren't that many secrets left to explore. But burgers are such a perfect blank canvas that they invite endless tinkering, and almost every celebrity chef has some secret burger ingredient they swear by. And for Alton Brown, that's a simple swipe of yellow mustard.

The real secret of using mustard with your burger isn't using it as a condiment, which is common enough. It's cooking the burger with mustard. Prior to making thin, smash-burger style sliders, as he revealed on his YouTube channel, Brown uses a spatula to smear a thin layer of yellow mustard on one side of the burger, then folds the meat over itself to seal in the mustard before cooking. The punchy condiment ends up seasoning the meat from the inside, adding extra flavor to simple sliders.

In-N-Out also cooks some of its burgers with mustard, but a little differently than Brown does. While the standard burger isn't cooked this way, there are two In-N-Out secret menu items, mustard-grilled and animal-style burgers, where the burger patty gets smeared with mustard on the top side as it cooks. Then, when the patty is flipped over, the second side sears directly in the mustard.

What makes mustard so special as a seasoning for burgers? It's all about balancing flavors. Burgers are a rich, umami food, and mustard has everything they lack in one ingredient. Your classic yellow mustard is made with salt, sugar, and vinegar, along with the namesake spice, so the fat of a burger gets a touch of seasoning, sweetness, and acid. That's a perfect recipe for a well-rounded bite of beef. And cooking the mustard with the meat is important, because then it does this much more subtly than using a bunch of mustard as a condiment. You should only be using a thin layer of mustard, and then the heat from cooking helps mellow its bite. You end up with a burger that still tastes like a burger, but with more mustardy complexity in the background.

The In-N-Out method that uses mustard on the outside of the burger also adds a second dimension that Brown's doesn't. When you sear the mustard on a griddle, it ends up caramelizing the mustard itself, in addition to the meat. That adds even more sweet, browned flavor to the patty. The mustard also forms a thin crust with the browned meat, adding a nice bit of texture as well. The heat transforms so much that someone else eating the burger might not even be able to tell there is mustard on it, but they will definitely demand to know how you made it.