Tear off 4 (18- x 12-inch) heavy-duty aluminum foil sheets.
Combine ground round and 1/4 cup barbecue sauce; shape into 4 patties.
Place 1 patty in center of each foil sheet; sprinkle evenly with salt and pepper. Top evenly with remaining 1/4 cup barbecue sauce, baby carrots, and remaining ingredients.
Bring up 2 sides of each aluminum foil sheet, and double fold with about 1-inch-wide folds. Double fold each end to form a packet, leaving room for heat circulation inside packet.
Grill, covered with grill lid, over medium-high heat (350° to 400°) 12 to 15 minutes on each side or until ground beef is no longer pink and vegetables are tender.