In and Out Burger Copycat Recipe: Secret Spread and Crispy Patties

Recreating that iconic West Coast flavor at home is simpler than you think. This recipe delivers the same crispy edges and mustard-grilled patties that made the original famous.

The secret lies in using fresh, never-frozen beef and a thin patty shape that ensures maximum caramelized crust. I tested this method with home cooks across different kitchens to perfect the texture.

What sets this apart is the signature spread—a thousand island variation that’s both tangy and slightly sweet. It’s the element that ties the whole burger together.

You’ll get that familiar, nostalgic taste in every bite, from the first crispy edge to the last drop of sauce. This is the closest you’ll get without driving to California.

Ingredients for In and Out Burger Copycat

Fresh beef, crisp lettuce, and that signature spread bring the West Coast classic to your kitchen.

The beef is non-negotiable here. 80/20 ground chuck from a trusted butcher or Whole Foods gives you the right fat for that caramelized crust. Look for bright red color with visible marbling—never pre-formed patties. The buns should be soft but sturdy enough to hold up to the juices (I grab Martin’s Potato Rolls when I can find them). American cheese might seem basic, but it melts like a dream.

No ground chuck? Ground sirloin with added butter can work in a pinch, but the texture won’t be the same. For the spread, substitute dill pickles for the relish if needed—just chop them super fine. The mustard can be Dijon for more bite, but yellow keeps it classic. If you’re skipping the cheese, add an extra slice of tomato to keep it juicy (trust me on this one).

Patties cook best the day they’re formed. Leftover spread keeps in the fridge for 5 days, though it’s so good you’ll use it up fast. The buns? Toast just before serving—1-2 days max in a bread box or they’ll stale. Prep all toppings ahead but assemble fresh.

Step-by-Step Instructions for In and Out Style Burgers

Here’s the method I use to nail that classic crispy texture and signature flavor at home.

Step 1: Make the Secret Spread

In a small bowl, combine the 0.5 cup mayonnaise, 0.25 cup ketchup, 2 tbsp sweet relish, and 1 tbsp yellow mustard. Stir until completely smooth with no visible streaks of relish.

I always let this spread sit for 10 minutes before using to let the flavors meld. This mimics the restaurant’s signature sauce perfectly. The relish gives it that sweet-tangy kick that balances the richness of the beef.

Step 2: Shape and Season the Patties

Divide the 1.5 lb ground chuck into 4 equal portions (about 6 oz each). Gently form into thin patties—press them slightly thinner in the center than at the edges. This prevents bulging during cooking.

Season both sides lightly with the 1 tsp salt and 0.5 tsp black pepper. Don’t overwork the meat or compact it too tightly; loose patties create those crispy edges we’re after.

Step 3: Cook the Patties for Maximum Crisp

Heat the 2 tbsp vegetable oil in a large skillet over medium-high heat until shimmering. Add the patties and cook undisturbed for 3-4 minutes until the edges are deep brown and crispy.

Flip once and immediately top each with a slice of the american cheese slices. Cook for another 2-3 minutes until the cheese melts completely and the second side develops the same crispy crust.

Step 4: Toast the Buns and Prep Toppings

While the patties cook, split the 4 whole hamburger buns and toast them face-down in the same skillet for 1-2 minutes until light golden brown. The residual beef fat adds incredible flavor.

Thinly slice the 1 whole white onion, slice the 2 whole tomatoes, and separate crisp leaves from the 1 whole iceberg lettuce. Drain the 0.5 cup dill pickle chips well to prevent soggy buns.

Step 5: Assemble the Burgers

Spread a generous layer of the secret spread on both sides of each toasted bun. Layer from bottom up: bun, lettuce, tomato, onion, cheese-topped patty, pickle chips, and finally the top bun.

Press down gently to compress slightly. The key is the crispy patty edges contrasting with the soft bun and cool toppings. Serve immediately while the patties are still hot and crispy.

Perfect Pairings for This Recipe

Classic Sides

Crispy shoestring fries are my go-to pairing—their thin cut mirrors the burger’s edges. Toss with 1 tsp paprika and ½ tsp garlic powder for extra flavor. I also love simple salted potato chips for that nostalgic diner feel. 🍟

Fresh Accompaniments

A cold iceberg wedge salad with creamy dressing balances the richness. Or try pickled jalapeños for heat lovers. The acidity cuts through the beef beautifully, and both options keep the West Coast vibe alive.

Drink Pairings

A frosty vanilla shake or Neapolitan shake is the classic choice. For adults, a crisp pilsner or light lager works perfectly. I prefer Modelo Especial—its clean finish complements the spread. 🍺

Dessert Options

End with chocolate chip cookies or a root beer float. The sweetness contrasts nicely with the savory burger. For a lighter finish, fresh strawberry shortcake keeps the meal feeling fresh and balanced.

Frequently Asked Questions