The In-n-Out Secret Menu Hack You Should Use On All Burgers

While In-n-Out's core menu is great, it can be made so much greater by taking advantage of their not-so secret menu, which includes the option to get your burger "mustard-grilled."

When you order a mustard-grilled burger, the cook will add a bit of mustard to your patty before flipping it on the grill. It's a great way to add some additional flavor.

The mustard is squirted on the face-up side, and then flipped. While the burger cooks, the mustard caramelizes and imparts its flavor into the patty itself.

In addition to adding a thin, crispy layer of texture to the burger patty, the meat absorbs a lot of the stronger flavors, leaving only a hint of mustard acidity on the palate.