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
- Preheat a greased grill to medium heat.
- In a bowl, toss sliced onions with olive oil, salt and pepper.
- Cook onion on grill until they are softened and browned, stirring often, about 10 minutes. Set onions aside while you grill the beef patties.
- 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.
- Top beef patties with swiss cheese during the last minute of cooking.
- To assemble burgers, add mayonnaise and mustard to buns and fill with lettuce, beef patties with cheese, and grilled onions.
- Serve burgers immediately.
- 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.