Preparation Steps

• In a bowl, gently mix the ground beef with Worcestershire sauce, salt, and pepper. Form into two patties.
• Heat olive oil in a skillet over medium heat. Add sliced onions and cook until caramelized, stirring occasionally, about 15-20 minutes. Remove from skillet and set aside.
• Melt butter in the same skillet over medium heat. Add the patties and cook for 4-5 minutes per side, or until cooked through and browned.
• Place Swiss cheese slices on top of each patty during the last minute of cooking to melt.
• Spread butter on the outside of each slice of rye bread. Place one slice of bread, butter-side down, in the skillet. Top with one patty, caramelized onions, and another slice of bread, butter-side up.
• Cook for 2-3 minutes per side, or until golden brown and the cheese is melted and gooey.
• Remove from skillet, slice in half, and serve immediately.