Heat gas or charcoal grill. Cut 4 (18x12-inch) sheets of heavy-duty foil; spray center of each with cooking spray. In large bowl, mix ground beef, seasoned salt and pepper. Shape mixture into 4 patties, 1/2 inch thick.
In center of each sheet of foil, place 1 cup potatoes, 1/4 of the vegetables and cheese sauce chips, and 1 beef patty. Wrap each packet securely using double-fold seals, allowing room for heat expansion.
Place packets, sealed side down, on grill; cover grill. Cook with medium heat 10 minutes. Turn packets over; cook covered 15 to 18 minutes longer or until thermometer inserted in center of patties reads 160°F and vegetables are tender.
To serve, carefully open packets to allow steam to escape. Stir to mix in cheese sauce.