Cut all fat off of chicken breasts, then pound with a meat mallet until very thin. Place one slice ham on top of each breast, then one slice cheese. Then place enough dressing on lower half of each chicken piece, fold over and secure with toothpicks.
Dip rolled/stuffed chicken breasts into buttermilk, then crumbs. Place coated chicken pieces in a 9x13 inch baking dish and put butter or margarine pieces around chicken. Cover dish with aluminum foil and bake in the preheated oven for about 1 1/2 to 2 hours or until chicken is cooked through and juices run clear. Remove cover for last 15 minutes to brown.
