Mushroom Swiss Burger Recipe

Form patties

Place ground beef in a large bowl. Add 1 tsp salt, 1/2 tsp black pepper, 1/4 tsp garlic powder, and 1 tablespoon Worcestershire sauce. Gently mix just until combined — avoid overworking. Divide into 2 equal portions and form into patties about 3/4-inch thick, slightly wider than buns. Make a shallow dimple in the center of each patty with your thumb to reduce puffing while cooking.

Cook patties

Heat a heavy skillet or griddle over medium-high heat and add 1 tsp vegetable oil. When the pan is hot and shimmering, place patties in the pan. Cook undisturbed for 3-4 minutes until a deep brown crust forms. Flip and cook 3 minutes more for medium (adjust time for desired doneness). During the last minute of cooking, reduce heat to medium-low, place 2 Swiss cheese slices (one per patty or split as desired) on top of the patties and cover pan with a lid to melt cheese, about 1 minute. Remove patties to a plate and tent with foil to keep warm.

Sauté mushrooms and onions

While patties rest or in a separate pan, heat 1 tablespoon butter and 1 teaspoon olive oil in a medium skillet over medium heat. Add sliced mushrooms and cook without stirring for 2 minutes to encourage browning, then stir and add the thinly sliced half onion. Continue cooking 4-5 minutes until mushrooms release moisture and both mushrooms and onions are nicely golden.

Season and finish

Add 1 teaspoon fresh thyme leaves (or 1/4 tsp dried), 1/2 tsp salt and 1/4 tsp black pepper. Pour in 2 tablespoons beef broth or water to deglaze the pan, scraping up browned bits. Cook until liquid reduces and the mixture is glossy, about 1-2 minutes. Reduce heat to low and stir in any juices from the resting patties if desired for extra flavor.

Combine with cheese (optional)

If you want the mushrooms to sit over the cheese, spoon the mushroom-onion mixture onto the cheese-melted patties just before assembling the burgers.

Toast buns

Spread 1 tablespoon softened butter evenly on the cut sides of the 2 buns. Place buns butter-side down in a clean skillet over medium heat and toast until golden, about 1-2 minutes. Remove and keep warm.

Prepare sauce

In a small bowl, stir together 2 tablespoons mayonnaise, 1 teaspoon Dijon mustard, and 1/4 tsp cracked black pepper. Taste and adjust seasoning.

Assemble burgers

Spread the mayo-Dijon sauce on both toasted bun halves. Place the cheese-topped patty on the bottom bun, spoon a generous portion of the mushroom-onion mixture over the patty, add optional lettuce or arugula if using, then cap with the top bun. Serve immediately.