Copycat In-N-Out Animal Style Burger

An In-N-Out Double-Double Animal Style costs about $5.50 — a steal for a restaurant burger. But if you don’t live near one of their limited locations (or you want to make a dozen for a cookout), this recipe nails the mustard-grilled patty, the sweet grilled onions, and that iconic spread for roughly $2.75 per burger. The three things that make Animal Style special: the patty is cooked with yellow mustard pressed directly into the griddle, the onions are grilled (not raw), and there’s extra spread on both buns.

Ingredients

For the Animal Style spread:

• 1/4 cup Hellmann’s mayonnaise
• 2 tablespoons Heinz ketchup
• 1 tablespoon sweet pickle relish (Vlasic)
• 1 teaspoon white distilled vinegar
• 1 teaspoon granulated sugar
• Pinch of salt

For the grilled onions:

• 1 large yellow onion, finely diced (1/4-inch pieces)
• 1 tablespoon unsalted butter
• Pinch of kosher salt

For the burgers:

• 1 1/4 lbs ground beef (80/20 chuck blend)
• 8 slices American cheese (Kraft or Land O’Lakes Deli)
• 4 hamburger buns (soft squishy style, like Trader Joe’s brioche or potato buns)
• Yellow mustard (French’s)
• Dill pickle chips (Claussen for extra crunch)
• Kosher salt and freshly ground black pepper
• 1 tablespoon butter for toasting buns

Instructions

1. Make the spread. Combine all spread ingredients in a bowl and stir until smooth. Refrigerate for at least 15 minutes. This keeps for a week and also works as a fantastic fry sauce.
2. Grill the onions. Melt 1 tablespoon butter in a skillet over medium heat. Add the finely diced onion and a pinch of salt. Cook for 15-20 minutes, stirring every 3-4 minutes, until the onions are deep golden brown, soft, and sweet. They should be jammy, not crunchy. Set aside.
3. Portion the beef. Divide the ground beef into 8 equal balls (about 2.5 ounces each) for double-double style. Gently shape into loose balls — do not pack them tightly.
4. Preheat your griddle. Get a cast iron skillet or flat griddle screaming hot over high heat for at least 5 minutes. The surface should be around 450-500°F.
5. Smash the patties. Place a beef ball on the griddle and immediately smash it flat with a sturdy metal spatula or burger press to about 1/4-inch thickness. Season the top with salt and pepper. Squirt a generous zigzag of yellow mustard across the top of each patty — about 1 teaspoon per patty.
6. Cook the mustard side. After 2-3 minutes, when the bottom has a deep brown, lacey crust, flip the patty so the mustard side hits the hot griddle. The mustard will sizzle and caramelize into a tangy, crispy crust. Immediately lay a slice of American cheese on top.
7. Second side. Cook for another 1-2 minutes until the cheese is melted and the bottom has a good sear. Remove to a plate.
8. Toast the buns. Butter the cut sides of the buns and toast them on the griddle for 30-45 seconds until golden brown.
9. Assemble Animal Style. Spread a generous tablespoon of spread on both the top and bottom bun. On the bottom bun, stack two cheesy patties. Add a layer of dill pickle chips and a generous spoonful of grilled onions. Close with the top bun.
10. Wrap and rest. Wrap each assembled burger in a square of wax paper or parchment and let it rest for 1-2 minutes. This steams the bun slightly and melds all the flavors together — just like the paper-wrapped burgers you get at In-N-Out.

Pro Tips

• The mustard grill is everything — do not skip it. This is the single most important technique that separates Animal Style from a regular cheeseburger. The mustard hits the hot griddle, caramelizes, and creates a tangy, slightly crispy layer that you cannot replicate any other way. Use French’s yellow mustard specifically — fancy Dijon won’t work here.
• Smash within 10 seconds. The moment the beef ball touches the griddle, you have a narrow window to smash it thin before the proteins set. If you wait too long, the patty will resist flattening and you’ll end up with a thick, uneven disc instead of a thin, crispy-edged patty.
• American cheese is non-negotiable. It’s the only cheese with the right melt, creaminess, and mild tang for this burger. Cheddar, Swiss, pepper jack — all wrong. American cheese was literally engineered to melt perfectly on a hot patty, and this is the dish where it earns its place.

The Michelin Twist

Want to take this from fast food to fine dining? Here’s how to elevate it:

• Duck fat-griddled patties with whole-grain mustard: Cook the smash patties in rendered duck fat instead of on a dry griddle, and replace the yellow mustard with Maille whole-grain Dijon. The duck fat adds a luxurious richness to the crust, while the whole-grain mustard pops with texture and a more complex, wine-forward tang.
• Cipollini onion confit: Instead of diced grilled onions, halve a dozen cipollini onions and slowly confit them in olive oil with thyme and garlic at 275°F for 90 minutes until they’re meltingly soft and caramelized throughout. The delicate sweetness of cipollini is more refined than yellow onion and adds an elegant layer.
• Milk bread bun with everything seasoning butter: Replace the standard bun with a homemade Japanese milk bread (shokupan) bun, toasted in butter mixed with everything bagel seasoning. The impossibly soft, slightly sweet milk bread paired with savory, seedy butter creates a bun that’s a destination in itself.

Cost Breakdown

Compare to $22.00 for four Double-Doubles Animal Style at In-N-Out — save 50%

Nutrition (Per Serving)

• Calories: 610
• Protein: 35g
• Fat: 38g
• Carbs: 32g