Heat gas or charcoal grill. Cut 18x18-inch sheet of heavy-duty foil. Spray foil with cooking spray. With 2 forks, shred thawed chicken.
Spread about half of chips evenly in center of sprayed foil. Top with half of the chicken and half of the cheese. Repeat layers. Wrap packet securely using double-fold seals, allowing room for heat expansion.
When grill is heated, place packet, seam side up, on gas grill over medium heat or on charcoal grill 4 to 6 inches from medium coals. Cook 10 to 15 minutes or until thoroughly heated and cheese is melted.
To serve, open packet carefully to allow steam to escape. If desired, top with chunky-style salsa, chopped tomato, diced avocado, chopped cilantro, sliced green onions, sour cream and/or guacamole.