How The Animal Style Burger At In-N-Out Was Actually Invented Will Make You Laugh

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While it is arguably the most iconic way you can eat anything at In-N-Out, the origin of Animal Style is actually rooted in more of an inside joke than a planned addition. In her book "The Ins-N-Outs of In-N-Out Burger", Lynsi Snyder, president and owner of the fast food chain, tells the story of how one particular customer saw a manager named Theo Roberts making a custom burger for himself. He asked if he could order the same kind.

After the customer tried it and liked it, he kept coming back to order it again. He didn't just ask for it once, he asked for it so many times that the staff eventually learned the order before the customer even had to explain it. To save time, Roberts decided to give it a name — Animal Style — and it not only stuck, it spread. And fast. What had started off as one customer's specific preferences quickly became one of the best (if not the best) items on In-N-Out's secret menu.

For the unfamiliar, Animal Style is the code word to have your burger patty fried in mustard (this gives it a sharper edge), then topped with all possible toppings including grilled onions (instead of raw), pickles, lettuce, tomato, and an extra lashing of In-N-Out's secret sauce. You can order it as a burger or, just as famously, as loaded fries. And it's so funny to think that one person's custom order could become quite so legendary.

For years, this little upgrade lived in the fun gray area between "not on the menu" and "everyone knows about it", so ordering it felt like being in on a secret (even if the person behind the counter had heard it a hundred times already). That dynamic lives on today: you still won't find it on the official menu in the restaurant, yet it's one of the most recognizable items from In-N-Out.

Animal Style likely became so popular simply because of how much every detail elevates the burger. The onions do more heavy lifting than they actually get credit for – low and slow cooked caramelized onions add a whole level of richness that raw onions just can't compete with. That richness then balances out the other sharper elements of the burger, such as the mustard-y patty and the extra sauce.

We can't forget about that extra sauce — there's a reason the sauce at In-N-Out is the stuff of legends, often copied but rarely matched. It's slightly sweet, a little tangy, and ties it all together. All it really took was to give this style a name for it to stop being a one-off order and to start feeling like it was always meant to be on the menu, without ever needing to be formally added. That's kind of powerful, when you really think about it.