Ingredients

Burger

• 2 tbsp butter
• 1 lb cremini mushrooms, sliced
• 2 lbs ground beef
• 2 garlic cloves, minced
• 1/2 red onion, grated
• 2 tsp horseradish (optional)
• 2 tbsp steak sauce (optional)
• Salt and pepper to taste
• 1 cup shredded Swiss cheese
• Toppings:
• 8 burger buns
• Lettuce
• Onion slices
• Tomato slices

Preparation

In a large frying pan, melt the butter over medium-high heat. Add the mushrooms and cook until they begin to brown, about 8 to 10 minutes. Set them aside.
In a large mixing bowl combine ground beef, garlic, red onion, horseradish, steak sauce, salt and pepper. Use your hands to mix well. Form 16 thin but uniform patties. Stuff 8 of the patties with mushrooms and Swiss cheese. Top each patty with a second patty and pinch the edges together to create 8 stuffed burgers. Grill burgers on both sides to your desired doneness. Place grilled burgers on buns and garnish with lettuce, onion and tomato.
Serve immediately or store in the refrigerator for up to 3 days.