In-N-Out-Style Double-Double (Copycat Recipe)

This is a homemade version inspired by the In-N-Out Double-Double, not the official recipe, and PlanetBurger is not affiliated with In-N-Out Burger. The appeal is simple: two thin, well-seared patties, two slices of melty American cheese, crisp lettuce, tomato, onion and a sweet-tangy spread on a toasted bun.

Thin patties cooked on a very hot surface give you plenty of browned crust in just a few minutes. If you want to go further, the Animal Style option below adds mustard-seared patties, grilled onions, pickles and extra spread. For more on the technique, see our ultimate smash burger and American burger styles explained.

1. Make the spread. Stir together the mayonnaise, ketchup, relish, vinegar and sugar. Refrigerate while you prep everything else.
2. Prep the toppings. Slice the tomato and onion and tear the lettuce. Have everything ready next to the stove, because the patties cook in minutes.
3. Grill the onions (Animal Style only). Melt the butter in a skillet over medium-low heat. Add the diced onion with a pinch of salt and a splash of water and cook, stirring often, until soft and deep golden, 20 to 25 minutes. Set aside.
4. Toast the buns. Heat a griddle or large cast-iron skillet over medium heat. Brush the cut sides of the buns with oil or butter and toast until golden, about 1 minute. Set aside.
5. Sear the patties. Raise the heat to high. Place the beef balls on the griddle in batches and press each firmly into a thin patty about 4 inches wide. Season with salt and pepper. Cook until well browned on the bottom, about 2 minutes.
6. Flip and add cheese. For Animal Style, spread about 1 teaspoon of mustard on the raw top of each patty before flipping. Flip, top each patty with a slice of cheese and cook about 1 minute more, until the cheese melts. The patties should reach 160°F (71°C).
7. Stack the doubles. Set one cheese-topped patty on top of another so each burger has two patties and two slices of cheese.
8. Assemble. Spread sauce on the bottom bun, then add tomato, lettuce, onion and the double patty stack. For Animal Style, skip the raw onion, add pickles under the patties and top with grilled onions and extra spread. Cap with the top bun and serve right away.

• Keep the beef cold. Cold balls of beef press thinner and hold together better on a hot griddle.
• Press once, early. Smash the patties in the first 30 seconds of cooking; pressing later squeezes out juice.
• Use a wide, sturdy spatula. A stiff spatula scrapes up the browned crust instead of leaving it stuck to the pan.
• Make the onions ahead. Grilled onions for Animal Style keep 3 to 4 days in the fridge and reheat in a minute.

Approximately 720 calories per serving. This is an estimate.