1Spray 12x8-inch (2-quart) glass baking dish and sheet of foil (large enough to cover dish) with cooking spray. In 12-inch nonstick skillet, cook ground beef over medium-high heat 5 to 7 minutes, stirring frequently, until beef is thoroughly cooked; drain.
2Stir in bell pepper and onion stir-fry, corn, chiles and taco seasoning mix. Cook 5 minutes, stirring frequently, until bell peppers and onions are tender. Stir in taco sauce. Remove from heat.
3Spoon half of beef mixture evenly in bottom of baking dish. Cover with 2 cups of the chips. Sprinkle 3/4 cup of the cheese over chips. Spoon remaining half of beef mixture evenly over cheese. Sprinkle with 1 cup cheese. Top evenly with remaining 1 cup chips. Cover baking dish tightly with foil, sprayed side down. Refrigerate at least 4 hours or overnight.
4When ready to bake, heat oven to 375°F. Bake casserole covered 20 minutes. Uncover; sprinkle with remaining 1/4 cup cheese. Bake uncovered 5 to 10 minutes longer or until casserole is thoroughly heated and cheese is melted. Cut into squares.