Brown 4 boneless chicken breasts in hot oil. Drain and cool. Slice 1 cup of fresh mushrooms. Mix with 1 can cream of mushroom soup and 1 cup sour cream. Place chicken breasts in greased 8 inch cake pan or small 1 1/2 quart casserole dish. Pour the mushroom mixture over the chicken. Bake at 350 degrees for 30-40 minutes or until bubbly.

Note: This is a great dish to make ahead and freeze the casseroles, then thaw and reheat.