Preheat grill to medium heat. Mix meat and 1/4 cup of the barbecue sauce. Shape into 6 patties.
Grill patties 6 to 8 minutes on each side or until cooked through (160°F), turning and brushing occasionally with the remaining 1/4 cup barbecue sauce for the last 5 minutes of the grilling time. Top each patty with 1 Singles; continue grilling 2 minutes or until Singles begin to melt.
Place lettuce and tomatoes on bottom halves of rolls; top with burgers, pickles and tops of rolls.