1 - pound lean ground beef
1/4 - teaspoon salt
1/8 - teaspoon pepper
1/2 - cup pesto
4 - Swiss cheese slices
4 - hamburger buns, split

• In a mixing bowl, add ground beef, salt and pepper. 
• Shape beef into patties, each about 3/4 inch thick. 
• Place patties on rack in broiler pan.
  
• Broil with tops 3 to 4 inches from heat 5 to 7 minutes on each side for medium, turning once, until no longer pink in center and juice is clear. 
• Spread patties with pesto. 
• Top each patty with a slice of cheese. 
• Broil just until melted.
  
• Serve patties in buns.