Mix coating mix and oregano in pie plate. Add 1 chicken breast; turn to evenly coat. Place in 13x9-inch pan sprayed with cooking spray. Repeat with remaining chicken breasts. Discard any remaining coating mixture.
Bake 15 minutes. Meanwhile, heat tomato sauce in saucepan on medium heat. Add cream cheese product; cook and stir 5 minutes or until cream cheese is melted and sauce is well blended. (Do not let sauce come to boil.)
Spoon sauce over chicken; top with shredded cheese. Bake 10 minutes or until chicken is done (170 degrees F) and cheese is melted.