In-N-Out Animal Style Burger
Mustard-grilled patty, caramelized onions, and that sauce. San Diego muscle memory. First liberty in San Diego after my first deployment, and the first place I went wasn’t a bar — it was In-N-Out. Dou
Ingredients
For the burgers
- 1 pound ground beef (80/20 chuck)
- kosher salt
- black pepper
- yellow mustard
- 4 slices American cheese
- 4 potato buns
For the spread
- 1/2 cup mayonnaise
- 2 tablespoons ketchup
- 2 tablespoons sweet pickle relish
- 1 teaspoon white vinegar
- 1/2 teaspoon sugar
For assembly
- Caramelized onions (1 large yellow onion
- thinly sliced)
- dill pickle slices
- iceberg lettuce
- tomato slices
Method
Step 1: Caramelize the onions
-
This is the longest step and the most important one to do first. Slice one large yellow onion thin. Cook in a tablespoon of butter over medium-low heat for 25-30 minutes, stirring occasionally, until deep golden and sweet. Season with a pinch of salt. These can be made a day ahead and reheated.
Step 2: Make the spread
-
Mix all sauce ingredients and refrigerate while you prep the burgers.
Step 3: Smash and mustard-grill the patties
-
Divide the beef into 8 loosely packed balls (about 2 ounces each). Heat a cast iron skillet or griddle until smoking hot. Place a ball on the surface, smash thin with a spatula. Season with salt and pepper. Cook 2 minutes. Spread 1 tablespoon yellow mustard on the raw side. Flip onto the mustard — you’ll hear it sizzle. Cook 1 minute more. Add a slice of American cheese and a spoonful of caramelized onions on top. Place a second cheesed patty on top of the first to create the double stack.
Step 4: Toast and assemble
-
Toast the buns in the beef fat. Spread sauce on both halves. Bottom bun: lettuce, tomato, pickle slices, double patty stack. Top bun. Press gently.
Off the Galley Mike
Mike — Off The Galley
Six years as a Navy cook on submarines and destroyers, feeding 130 sailors from a galley the size of your bathroom. Now I cook the same big-flavor, no-nonsense food for my family of four — and share every recipe here. No culinary school. No fancy plating. Just real food that works, tested on the toughest critics afloat and the pickiest ones at home.
In-N-Out Animal Style Burger — Mustard-Grilled, Smashed, and Worth Every Napkin
Mustard-grilled patty, caramelized onions, and that sauce. San Diego muscle memory. First liberty in San Diego after my first deployment, and the first place I went wasn’t a bar — it was In-N-Out. Double-Double Animal Style. I still remember the first bite. Six months of galley food, and then THIS. Changed my entire understanding of what a burger could be. Thin, crispy, tangy, and absolutely covered in caramelized onions and that sauce.
If you’ve never been to an In-N-Out, the Animal Style burger isn’t on the printed menu. It’s from their not-so-secret secret menu, and it means: mustard-grilled patties, extra pickles, grilled onions, and extra spread. The mustard goes directly on the raw side of the patty before you flip it, so it caramelizes into the meat. This is the detail that elevates a regular smash burger into something transcendent.
The Mustard-Grilled Technique
This is the move that separates Animal Style from every other burger. While the patty is cooking on the first side, spread about a tablespoon of plain yellow mustard on the raw top. When you flip, the mustard hits the hot surface and caramelizes with the beef juices and fat. The result is a tangy, almost-crispy crust that you cannot replicate any other way. Don’t use Dijon or fancy mustard — plain yellow French’s is exactly right. The mild tanginess is the whole point.
The Spread (Special Sauce)
In-N-Out’s spread is essentially Thousand Island dressing with a few adjustments. Mix 1/2 cup mayo, 2 tablespoons ketchup, 2 tablespoons sweet pickle relish, 1 teaspoon white vinegar, and 1/2 teaspoon sugar. Let it sit in the fridge for 30 minutes. It’s not complicated, but making it fresh means you control the quality, and it tastes noticeably better than bottled dressing.
Ingredients
For the burgers: 1 pound ground beef (80/20 chuck), kosher salt, black pepper, yellow mustard, 4 slices American cheese, 4 potato buns.
For the spread: 1/2 cup mayonnaise, 2 tablespoons ketchup, 2 tablespoons sweet pickle relish, 1 teaspoon white vinegar, 1/2 teaspoon sugar.
For assembly: Caramelized onions (1 large yellow onion, thinly sliced), dill pickle slices, iceberg lettuce, tomato slices.
How to Make It
1
1Caramelize the onions
This is the longest step and the most important one to do first. Slice one large yellow onion thin. Cook in a tablespoon of butter over medium-low heat for 25-30 minutes, stirring occasionally, until deep golden and sweet. Season with a pinch of salt. These can be made a day ahead and reheated.
2
2Make the spread
Mix all sauce ingredients and refrigerate while you prep the burgers.
3
3Smash and mustard-grill the patties
Divide the beef into 8 loosely packed balls (about 2 ounces each). Heat a cast iron skillet or griddle until smoking hot. Place a ball on the surface, smash thin with a spatula. Season with salt and pepper. Cook 2 minutes. Spread 1 tablespoon yellow mustard on the raw side. Flip onto the mustard — you’ll hear it sizzle. Cook 1 minute more. Add a slice of American cheese and a spoonful of caramelized onions on top. Place a second cheesed patty on top of the first to create the double stack.
4
4Toast and assemble
Toast the buns in the beef fat. Spread sauce on both halves. Bottom bun: lettuce, tomato, pickle slices, double patty stack. Top bun. Press gently.
Why It Works
The combination of mustard-grilled beef, melted American cheese, sweet caramelized onions, tangy-sweet sauce, and crisp pickles creates a layered flavor experience where every bite has something different happening. The mustard crust adds an acidic brightness that cuts through the richness of the beef and cheese. The caramelized onions add sweetness. The pickles add crunch. It’s a masterpiece of fast food engineering, and it translates perfectly to the home kitchen.
Pair It With
Animal Style fries are the traditional pairing — fries topped with melted cheese, caramelized onions, and the spread. A Frosty or chocolate milkshake completes the California drive-through experience. Add a regular smash burger for guests who prefer their burgers less saucy.
The San Diego Connection
Every sailor who’s been stationed in San Diego has an In-N-Out story. It’s practically a rite of passage — you get off the ship, you drive straight to the nearest In-N-Out, and you order Animal Style. The line is always long because every other sailor had the same idea. My first time, the guy at the window looked at my uniform and said “Double-Double Animal Style?” before I even opened my mouth. He knew. Everyone knows. If you’ve never been to California, this recipe is your entry point. If you have been, this recipe is your way back.
Common Mistakes
Using Dijon instead of yellow mustard changes the flavor profile completely — stick with yellow. Not getting the skillet hot enough before smashing means you won’t get proper browning. Skipping the caramelized onions and using raw onions instead misses the point entirely — the sweetness of the cooked onions is essential. And don’t rush the onions; 10 minutes of sautéing gives you softened onions, not caramelized ones. You need the full 25-30 minutes for the sugar to develop.
Storage
The spread keeps for up to a week in the fridge. Caramelized onions last 5 days refrigerated or can be frozen for a month. Cook the patties fresh — they don’t reheat well because the mustard crust loses its crispiness.
Frequently Asked Questions
What does “Animal Style” actually mean?
At In-N-Out, it means mustard-grilled patties, extra spread, grilled onions, and extra pickles. You can also order fries Animal Style (topped with cheese, onions, and spread).
Can I make this on a regular grill?
Use a cast iron skillet or griddle on the grill — not directly on grates. The mustard and cheese will fall through grates, and you need flat surface contact for the smash technique.
Is this really how In-N-Out makes theirs?
The technique is authentic — mustard on the raw side, flip, cheese and onions on top. The exact spread recipe is proprietary, but this version is remarkably close to the original.
The Spread That Makes It
Animal style spread is the secret weapon. It’s essentially a Thousand Island variant: mix mayo, ketchup, sweet pickle relish, and a tiny splash of vinegar. The spread goes on both bun halves and provides the tangy, creamy, slightly sweet element that ties the entire burger together. Without the spread, it’s just a burger with grilled onions and mustard. With the spread, it becomes something distinctive and craveable.
Mustard-Grilled Patty Technique
The “mustard-grilled” step is what separates animal style from a regular cheeseburger. Squirt yellow mustard directly onto the raw side of the patty while the first side cooks, then flip. The mustard hits the hot cooking surface and caramelizes, creating a tangy crust that’s barely perceptible as mustard but adds a layer of flavor complexity that’s hard to identify but unmistakably present. This technique takes 2 seconds and adds significant depth to the flavor profile.
More From Off The Galley
Smash Burgers · Chick Fil A Sandwich · Big Mac Copycat · Wendys Frosty · Cauliflower Mac
Off the Galley Mike
Mike — Off The Galley
Six years as a Navy cook on submarines and destroyers, feeding 130 sailors from a galley the size of your bathroom. Now I cook the same big-flavor, no-nonsense food for my family of four — and share every recipe here. No culinary school. No fancy plating. Just real food that works, tested on the toughest critics afloat and the pickiest ones at home.