Mushroom Swiss Burger Recipe

Make the spiced mayo

In a small bowl combine 1/2 cup mayonnaise, 1 tsp Dijon mustard, 1/2 tsp hot sauce (or smoked paprika), 1/2 tsp lemon juice, 1/4 tsp garlic powder, 1/4 tsp smoked paprika and 1/8 tsp salt. Whisk until smooth. Taste and adjust heat or acidity. Refrigerate while you prepare the rest so flavors meld.

Prepare and sauté mushrooms

Heat a large skillet over medium-high heat. Add 1 tbsp olive oil and 1 tbsp butter until shimmering. Add the sliced mushrooms in a single layer (work in batches if necessary) and sear without stirring for 2 minutes to develop color. Stir and continue cooking 3–4 minutes until mushrooms are golden and their liquid has mostly evaporated.

Add 1 tbsp minced shallot and 1 tsp minced garlic to the mushrooms and cook 30–45 seconds until fragrant. Sprinkle 1 tsp fresh thyme leaves over the mushrooms.

Deglaze the pan with 2 tbsp dry white wine or chicken stock, scraping up browned bits. Stir in 1 tsp soy sauce, 1/2 tsp salt and 1/4 tsp black pepper. Cook 1–2 minutes until liquid reduces to a glossy coating. Remove from heat and keep warm.

Season and cook patties

Divide beef into two 8 oz patties (if not preformed) and gently shape to about 3/4" thick, making a slight indentation in the center with your thumb to prevent doming. Season both sides with 1/2 tsp kosher salt and 1/2 tsp freshly ground black pepper (total 1 tsp salt and 1 tsp pepper across both patties).

Preheat a cast-iron skillet or grill over medium-high heat until very hot. Add a light coating of oil or fat. Place patties on the hot surface and cook undisturbed 3–4 minutes per side for medium (adjust time for desired doneness). During the last minute of cooking, place 1 slice Swiss cheese on each patty and cover the pan or close the grill lid to melt the cheese, about 1 minute.

While patties rest 3–4 minutes, spread 1 tbsp butter on each cut side of the brioche buns and toast buttered sides in a skillet or on a griddle over medium heat until golden, about 1–2 minutes.

Assemble each burger: spread about 1.5 tbsp spiced mayo on the bottom bun, top with a small handful (about 1/2 cup) arugula, place the Swiss-topped patty on top, spoon about 1/4 of the warm wild mushroom sauté over the cheese, add optional pickle slices or red onion if using, and finish with the top bun smeared with remaining mayo if desired.