4 skinned and boned chicken breasts
1 pkg. (4 oz.) chopped beef
1 pt. (small) sour cream
1 can undiluted mushroom soup

Cover bottom of 8 x 12 dish with broken pieces of beef. Arrange chicken breasts on beef. Mix soup and sour cream and pour over chicken. Melt 3/4 cup butter and mix with 45 crushed Ritz crackers. Put on top of chicken. Refrigerate. When ready, bake at 275 degrees for 4 hours uncovered. If too brown the last hour, cover with foil.