AIP Friendly Mushroom & Caramelized Onion Burger

Total time1 hr

Prep time20 min

Cook time40 min

AIP Friendly Mushroom & Caramelized Onion Burger

Burger night doesn't have to feel like a compromise, and this recipe proves it in the most satisfying way possible. An 80/20 beef patty seasoned with sea salt, ginger, and thyme gets a serious sear in coconut oil, building that deep, caramelized crust that makes a great burger what it is. The real showstopper is the topping — slow-cooked onions that go jammy and golden over 25 to 30 minutes, piled high with sautéed cremini mushrooms and finished with a splash of apple cider vinegar for brightness. Then there's the Swiss-style sauce: a silky blend of full-fat coconut milk, arrowroot starch, and turmeric that thickens into something genuinely creamy and rich without a drop of dairy. Skipping nightshades, grains, eggs, and legumes is notoriously tricky when you're craving comfort food, but every element here is built from protocol-friendly ingredients that don't feel like substitutes — they feel intentional. Serve the whole thing wrapped in a cassava flour tortilla or a crisp butter lettuce leaf, and you've got four hearty, crowd-pleasing plates that nobody at the table will feel shortchanged by.

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Ingredients

4 servings

For the patties

1 ½ lb ground beef (80/20)
Kroger Ground Beef 80/20 Simple Truth 80% Lean Natural Ground Beef Harris Teeter Premium 80% Lean Ground Beef SunFed Ranch 100% Grass Fed 80% Lean Organic Ground Beef Brick Kroger 80/20 Ground Beef
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1 tsp fine sea salt
½ tsp ground ginger
½ tsp dried thyme
1 tbsp coconut oil

For the mushroom & onion topping

2 medium yellow onions, thinly sliced
8 oz cremini mushrooms, thinly sliced
2 tbsp olive oil
½ tsp fine sea salt
1 tbsp apple cider vinegar

For the Swiss-style sauce

½ cup full-fat coconut milk
2 tsp arrowroot starch
1 tsp apple cider vinegar
¼ tsp ground turmeric
¼ tsp fine sea salt

For serving

4 cassava flour tortillas butter or large butter lettuce leaves
1 cup arugula or shredded romaine (optional)

Instructions

1
Heat 2 tbsp olive oil in a large skillet over medium-low heat. Add the sliced onions and 1/2 tsp salt, stirring to coat. Cook, stirring every 5–7 minutes, for 25–30 minutes, until the onions are deeply golden, jammy, and reduced to about one-third of their original volume.
2
Push the caramelized onions to one side of the skillet and increase the heat to medium-high. Add the sliced mushrooms in a single layer and cook undisturbed for 3 minutes, until the undersides are golden. Stir and cook for another 2–3 minutes, until the mushrooms are tender and any released liquid has evaporated. Stir the mushrooms together with the onions, add 1 tbsp apple cider vinegar, and cook for 30 seconds, until the vinegar is absorbed. Transfer the topping to a bowl and set aside.

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