Heat oven to 400°F. Spray large cookie sheet with cooking spray.
In large resealable food-storage plastic bag, place taco seasoning mix. In shallow bowl, beat egg. In another large resealable food-storage plastic bag, place bread crumbs. Place chicken in taco seasoning mix bag; seal and shake to coat. Dip chicken into egg. Place chicken in bread crumb bag; seal and shake to coat. Place chicken on cookie sheet.
Bake 15 to 20 minutes, turning once, until chicken is no longer pink in center and bread crumbs are golden brown. Serve with salsa.