Bistro Cheeseburger

Directions:

1. Preheat grill to medium heat.
2. Lightly shape ground beef into four 3/4-inch thick patties.
3. Brush onion with oil.
4. Place patties in center of grill; arrange onion around patties.
5. Grill, uncovered to desired doneness or until patties are not pink in center and juices show no pink color and onions are tender, turning occasionally.
6. Season with salt and pepper after turning.
7. About 1 minute before patties are done, top each with 2 cheese slices.
8. Combine mayonnaise and mustard; spread on top halves of rolls.
9. Serve burgers and onion in rolls with lettuce and tomato.