Ingredients

• 1 pound ground sirloin
• 1 tablespoon Worcestershire sauce
• 2 cloves garlic , minced, or more to taste
• 0.5 teaspoons salt
• 0.5 teaspoons ground black pepper
• 3 tablespoons unsalted butter
• 3 tablespoons olive oil
• 2 medium onions , sliced
• cooking spray
• 4 slices Cheddar cheese
• 4 teaspoons Dijon mustard , Optional
• 8 slices rye bread , lightly toasted

Instructions

1. 1 Mix sirloin, Worcestershire sauce, garlic, salt, and pepper together by hand in a medium bowl. Form into 4 hamburger patties and wrap in plastic wrap. Place in the refrigerator until flavors have melded, 4 hours to overnight.
2. 2 Heat butter and olive oil in a large skillet over medium heat until melted. Add onions and saute until they begin to caramelize, about 15 minutes, reducing heat to medium-low if they seem to be sizzling too much.
3. 3 Spray a large skillet with cooking spray and heat over medium heat. Place hamburger patties in the skillet and cook for 3 minutes per side, topping each patty with a slice of Cheddar cheese after flipping.
4. 4 Place patties on toasted rye bread. Top with warm onions, Dijon mustard, and remaining bread.

Nutrition per serving