In a skillet, cook beef over medium heat until no longer pink; drain. Stir in soup. Sprinkle 1 1/2 cups tortilla chips in a greased shallow 2 1/2-quart baking dish. Top with beef mixture, salsa and cheese.
Bake, uncovered, at 350 degrees for 25–30 minutes or until bubbly. Sprinkle with the remaining chips. Bake 3 minutes longer or until chips are lightly toasted.