1. Heat coals or gas grill for direct heat. Spray two 30x18-inch pieces of heavy-duty aluminum foil with cooking spray. Spread tortilla chips on centers of foil pieces. Mix sausage, chilies and seasoning mix; spoon over tortilla chips. Top with tomatoes and onions. Sprinkle with cheese.
2. Wrap foil securely around tortilla chips. Cover and grill foil packets, seam sides up, 4 to 6 inches from medium heat 8 to 10 minutes or until cheese is melted