• 1 1/2 lbs ground beef
  • 4 slices sweet onions , 1/2 in. thick
  • 8 slices swiss cheese
  • 1/4 cup mayonnaise
  • 1 tablespoon Dijon mustard
  • 4 crusty rolls , split and toasted
  • 4 slices cooked crisp bacon , halved
  • tomato , sliced
  • lettuce
  • 1 Preheat grill to medium. Lightly shape ground beef into four 3/4-inch thick patties.
  • 2 Brush onion slices with vegetable oil.
  • 3 Place patties in center of grid; surround with onions.
  • 4 Grill, uncovered and turning occasionally, 13 to 15 minutes for medium doneness (internal temp 160°F) or until patties are no longer pink in center and onions are tender.
  • 5 Season with salt and pepper to taste.
  • 6 About 1 minute before patties are done, top each with 2 cheese slices.
  • 7 Combine mayonnaise and mustard; spread on top halves of rolls.
  • 8 Serve burgers and onion in rolls with lettuce, tomato and crisp cooked bacon slices.