01 -
Season the ground beef with salt and pepper. Form into 2 patties. In a skillet, cook the patties over medium heat until browned on both sides and cooked to your desired doneness. Remove and set aside.
02 -
In the same skillet, add olive oil. Sauté the mushrooms and onions until softened and golden brown. Remove and set aside.
03 -
Layer each slice of rye bread with a beef patty, sautéed mushrooms and onions, and a slice of Swiss cheese. Top with another slice of rye bread.
04 -
In the skillet, melt butter over medium heat. Grill the sandwiches until golden brown on both sides and the cheese is melted.
05 -
Slice the sandwiches in half and serve warm.