What Is A Mustard Burger At In-N-Out?

In-N-Out Burger is a Southern California-based restaurant chain that has reached cult status. Despite its exceptionally small menu and limited number of possible burger toppings, fans swear by the juicy burgers, fresh-cut french fries, and superb milkshakes. Anthony Bourdain famously stated that whenever he traveled to Los Angeles, the first stop he made was In-N-Out — his favorite restaurant in the City of Angels (via CBS Los Angeles). Culinary queen Ina Garten, who doesn't ever eat fast food, admitted to People that the chain — which was also a favorite of Julia Child — was the one exception.

While the chain seemingly does not offer a lot of options, people in the know are familiar with its "secret menu," which includes things like a grilled cheese (basically, the cheeseburger without the meat) and the notorious "animal style" you can add to burgers and fries.

There are plenty of other ways to change up the norm at the eatery, which have been happily shared by its devoted fans across the internet. You can request your bun to be extra-toasted, your fries to be well-done, and your burger to be mustard-grilled. Just request a mustard burger during your next trek to In-N-Out and prepare to be wowed once again at this place that never disappoints.

Here's a little secret: Nothing on In-N-Out's standard menu comes with mustard on it. You always have to request it. When you ask for a mustard burger, the restaurant begins by placing a fresh patty on the griddle. Right before it's flipped to cook the other side, mustard is spread on the uncooked side. When the patty is flipped, the condiment seeps in, adding a delicious tangy twist to the caramelized meat. Mustard burgers also come with pickles for an additional sour kick and crunch. 

The only other way to get a mustard-grilled patty is to order your sandwich in the aforementioned "animal style." It's made the same way and adorned with pickles, but grilled onions and extra sauce are added in as well.

Since In-N-Out opened in 1948, its original hamburgers and cheeseburgers have become famous. These classics include a meat patty, iceberg lettuce, tomato slices, raw onions, and signature sauce, but they generally don't come with bacon, mushrooms, avocado, mayo, or mustard. These menu items are still delicious as they are. Opting for a mustard-grilled patty just takes the flavor up a notch.