Ingredients

  • 4 (1/4 lb) frozen beef patties (80% lean, 20% fat)
  • 1 yellow oniopn, thinly sliced
  • 1 tablespoon olive oil
  • 1/2 teaspoon salt
  • 1/4 teaspoon ground black pepper

 

  • 4 slices swiss cheese
  • 4 hamburger buns
  • Mayonnaise
  • Mustard
  • Chopped lettuce

Directions

  1. Preheat a greased grill to medium heat.
  2. In a bowl, toss sliced onions with olive oil, salt and pepper.
  3. Cook onion on grill until they are softened and browned, stirring often, about 10 minutes. Set onions aside while you grill the beef patties.
  4. Cook beef patties until charred and fully cooked through, about 4-5 minutes per side. Adjust grill temperature as needed. Internal temperature should register 160°F on an instant read thermometer.
  5. Top beef patties with swiss cheese during the last minute of cooking.
  6. To assemble burgers, add mayonnaise and mustard to buns and fill with lettuce, beef patties with cheese, and grilled onions.
  7. Serve burgers immediately.
  8. Notes: If your grill has wide grates, cook onions in a grill basket or on a greased sheet of aluminium foil. No need to thaw beef patties before cooking.