Swiss Mushroom Burger Recipe

Clean mushrooms with a damp towel or brief rinse; pat dry. Slice mushrooms evenly (about 1/4" thick).

Heat a large skillet over medium-high heat. Add 1 tsp olive oil and 1 tbsp butter. When butter foams, add minced shallot and cook 30–45 seconds until fragrant.

Add sliced mushrooms in a single layer (work in batches if necessary). Let mushrooms sit undisturbed 2–3 minutes to brown, then stir and continue cooking 3–4 minutes until golden.

Add minced garlic and thyme; cook 30–45 seconds until fragrant. Stir in Worcestershire sauce, salt and black pepper. Taste and adjust seasoning. Remove from heat and keep warm.

In a small bowl combine 1/2 cup mayonnaise, 1 minced garlic clove, 1 tbsp lemon juice, 1/2 tsp lemon zest, 1/2 tsp Dijon mustard, 1/4 tsp salt and 1/4 tsp pepper.

Whisk until smooth. If aioli is too thick, whisk in up to 1 tsp olive oil or a little water to reach desired spreading consistency. Refrigerate until ready to assemble (can be made up to 24 hours ahead to let flavors meld).

Remove patties from refrigerator about 15–20 minutes before cooking to come closer to room temperature. Pat dry with paper towel. Season both sides generously with kosher salt and freshly ground black pepper.

Heat a cast-iron skillet or heavy griddle over medium-high heat. Add 1–2 tbsp neutral oil and let shimmer.

Place 8 oz Wagyu patties in the hot skillet. For medium-rare to medium doneness, cook 4–5 minutes on the first side without pressing. Flip once and cook another 3–4 minutes for medium-rare to medium. Adjust time for desired doneness. If using a thinner patty or different heat, monitor internal temperature (130–135°F for medium-rare, 140°F for medium).

About 1 minute before the patties are done, place a slice of Swiss cheese on each patty and cover the skillet with a lid or tent with foil to melt the cheese, about 30–60 seconds.

Remove patties to a resting plate and let rest 2–3 minutes while you finish bread and assemble.

Butter one side of each sourdough slice lightly. Heat a separate skillet or griddle over medium heat. Toast buttered side down until golden and crisp, about 1–2 minutes. If you prefer cross-hatched grill marks, use a hot grill pan.

Spread about 1–1.5 tablespoons lemon garlic aioli on the inside (untoasted) side of the bottom slice of sourdough. Place the rested patty with melted Swiss on the aioli.

Top the cheese with 3–4 tablespoons sautéed mushrooms per burger, then a tomato slice, and optional lettuce or arugula if using. Add another 1 tablespoon aioli to the inside of the top slice of sourdough and place on top, aioli side down.

Press gently, cut in half if desired, and serve immediately while hot. Serve with fries or a simple salad.