HEAT barbecue for indirect grilling: Light one side of barbecue, leaving other side unlit. Close lid; heat barbecue to 350ºF.
DOUBLE fold edges of large sheet of heavy-duty foil to make rimmed 12x10-inch "tray." Spread chips onto bottom of tray; cover with cheese, onions and peppers. Place on grate over unlit area; cover. Grill 5 min. or until cheese is melted.
TOP with tomatoes. Serve with sour cream.
serving size = 1/8 recipe (92 g)