Preheat oven to 400 degrees. Spray a two 9 x 13-inch pan with cooking spray.
In a food processor, pulse the Ritz crackers into fine crumbs.
If using chicken breasts and not tenders, cut each chicken breast into 3 pieces. If chicken tenders are too thick, pound to flatten slightly.
Pour the milk, shredded cheese, and cracker crumbs into 3 separate shallow pans. Add salt and pepper to the cracker crumbs, stir to combine.
Dip each piece of chicken into the milk, followed by the cheese, pressing the cheese into the chicken with your fingers. Finally, press the cheesy coated chicken into the cracker crumbs with your fingers to coat.
Lay the chicken inside the prepared pans, do not over crowd. Sprinkle the chicken with dried parsley.
Cover the pan with foil and bake for 35 minutes. Remove the foil, bake for an additional 10-12 minutes, or until the edges of the chicken are golden brown and crispy.
SAUCE: In a sauce pan, combine the cream of chicken soup, sour cream, and butter with a whisk. Stir it over medium high heat until the sauce is nice and hot. Serve over the chicken.