1 tablespoon ketchup
1/2 cup fat free mayonnaise
salt to taste
freshly ground black pepper
1 pound lean ground beef sirloin
1 tomato, sliced
In a small bowl, stir the ketchup and mayonnaise together. Season to taste with salt and pepper.
Preheat the grill to medium-high.
Shape the ground sirloin into 4 patties, about 1/2-inch thick.
Season the patties with salt and pepper.
Grill the patties on both sides until the burgers are just cooked through, about 5 minutes per side.
Toast the rolls on the grill.