Heat oven to 400°F. Line cookie sheet with foil; spray foil with cooking spray.
Place chips in resealable food-storage plastic bag; crush with rolling pin. In shallow bowl, mix crushed chips and cheese. In another shallow bowl, beat egg and milk well. Dip chicken into egg mixture, then roll in chips mixture to coat. Place pieces 1 inch apart on cookie sheet.
Bake 10 to 12 minutes or until coating is light golden brown and chicken is no longer pink in center. Serve with ketchup.