Mushroom Swiss Cheese Burger Recipe

In a small bowl combine mayonnaise, minced shallot, lemon juice, Dijon, grated garlic, salt and pepper. Stir until smooth. Taste and adjust salt or lemon. Cover and refrigerate at least 15 minutes to let flavors meld.

Clean mushrooms by wiping with a damp cloth and slice thinly.

Heat a 10–12-inch skillet over medium-high heat. Add butter and olive oil. When butter foams, add sliced mushrooms in a single layer (do not overcrowd; do in batches if needed).

Let mushrooms brown undisturbed for 2–3 minutes, then stir and continue cooking 2–3 minutes until nicely caramelized.

Add minced garlic and thyme, cook 30–45 seconds until fragrant. Season with 1/2 tsp salt and 1/4 tsp black pepper. Remove from heat and set aside. Keep warm.

Divide the ground beef into four 4-ounce balls (this recipe yields two double patties; each burger gets two patties). Do not overwork the meat; gently shape into loose balls.

Preheat a heavy skillet or cast-iron griddle over high heat until smoking slightly. Add 1 tablespoon vegetable oil and spread.

Working one burger at a time, place two meat balls on the hot surface (for one sandwich) leaving space between. Immediately press each ball flat with a sturdy spatula or a heavy press to about 1/4-inch thickness. Hold pressure for 10–15 seconds to set edges. Season the exposed surface with a light sprinkle of kosher salt and black pepper.

Cook without moving until edges are brown and lacy, about 2–3 minutes. Flip each patty, quickly place a slice of Swiss cheese on each patty, and cook another 45–60 seconds until cheese melts and patties are cooked through. Repeat for the second burger.

While cooking the second set of patties, split buns and butter the cut sides. Toast buttered sides in a clean skillet or grill until golden, about 30–60 seconds.

To assemble each burger: spread about 1–2 tablespoons onion aioli on the bottom bun, place a small handful (about 1/2 cup) of arugula, stack the two hot Swiss-topped patties (one on top of the other), spoon a generous portion (about 3 tablespoons) of sautéed mushrooms over the patties, spread a thin layer of aioli on the top bun if desired, and place bun top.

Serve immediately with fries on the side.

Prepare fries according to package instructions or your preferred method. Season with salt immediately after cooking and serve alongside burgers.