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Whole30 In N Out double double animal style burgers in lettuce buns

Healthier In N Out Burgers: Double Double Animal Style

Two thin beef patties brushed with mustard, loaded with pickle slices, deeply caramelized onions, a creamy special sauce, all sandwiched between two perfect iceberg lettuce buns. Paleo, Whole30, and low carb friendly.

Course Main Course
Cuisine American, Paleo, Whole30
Keyword burger, healthy, in an out
Prep Time 5 minutes
Cook Time 35 minutes
Total Time 40 minutes
Servings 2 burgers
Calories 899 kcal



  1. Make the sauce: combine mayonnaise, ketchup, dill relish, coconut aminos, maple syrup (if not on Whole30), and vinegar in a small bowl. Stir to combine and chill while you continue cooking.
  2. Heat 2 teaspoons avocado oil in a medium skillet (preferably non-stick) over medium-high heat until oil is shimmering. Add onions and 3/4 teaspoon salt. Reduce heat to medium-low, and cook, stirring occasionally until onions are browned, about 15 minutes. Once onions are browned, they will start to sizzle and look dry. Add 1 tablespoon water to skillet and stir, cooking until water evaporates and onions begin sizzling again. Repeat the process with 1 tablespoon water until onions are dark brown and extremely caramelized, about 3 times, a total of about 30 minutes. Transfer to a bowl and let cool.
  3. Make the lettuce “buns”: slice off the stem of the head of iceberg lettuce, about 1/2-3/4”. Cut into fourths: down the center, then slice each half in half to make wedges. Take out the middle 2/3 of each iceberg wedge, so it leaves just a 3/4” thick lettuce “bun”. Set aside.
  4. Shape ground beef into four 2-ounce patties that are very thin and very wide, about 1/4" thick and at least 4" wide. Season patties with plenty of salt and pepper. Heat remaining 1 teaspoon avocado oil to a large cast-iron skillet over medium-high heat; swirl the oil around the pan to coat with a thin layer. When the oil is very, very hot, add burger patties. Spread 1 tablespoon mustard on the top, raw side. Cook patties, without moving, until they're very well browned and a bit crusty on the bottom, about 2-3 minutes. Flip patties so the mustard side is down and cook 30 seconds to 1 minute.
  5. Prepare your burgers: for each burger, spread about scant 1 tablespoon of animal sauce onto the inside of one lettuce "buns". Top with 2 pickles, then one slice tomato. Top with a burger patty and about 1 tablespoon caramelized onions, plus more if you like. Top with another burger patty and another 1 tablespoon caramelized onions. Top with another scant 1 tablespoon of sauce then the final lettuce bun. Wrap in parchment paper or aluminum foil and devour!

Recipe Video

Recipe Notes

This recipe makes enough caramelized onions and animal sauce to serve on top of some homemade sweet potato fries or hash. You will have extra besides what you need for the burgers.

Note that you MUST omit the maple syrup in the sauce for this recipe to be Whole30. 

For keto, omit all coco aminos and maple syrup and sweeten the sauce with 

My Whole30 immersion blender mayonnaise recipe: https://40aprons.com/whole30-immersion-blender-mayo/

My Whole30 ketchup recipe: https://40aprons.com/whole30-ketchup-recipe/

Adapted from the geniuses at Serious Eats.

Nutrition Facts
Healthier In N Out Burgers: Double Double Animal Style
Amount Per Serving
Calories 899 Calories from Fat 657
% Daily Value*
Fat 73g112%
Saturated Fat 16g100%
Cholesterol 104mg35%
Sodium 2317mg101%
Potassium 1050mg30%
Carbohydrates 36g12%
Fiber 7g29%
Sugar 20g22%
Protein 26g52%
Vitamin A 1781IU36%
Vitamin C 21mg25%
Calcium 129mg13%
Iron 5mg28%
* Percent Daily Values are based on a 2000 calorie diet.