Clean thoroughly and chill. Rub with soft butter, salt and dust with flour. Place breast side up on rack in roaster. Roast uncovered in hot oven 450 degrees about 20 minutes or until light brown, then reduce heat to 325 degrees and roast until tender. Baste frequently with drippings from pan or use a mixture of butter and hot water. Allow about 20 to 25 minutes per pound for cooking. Turn with breast down the last 25 minutes of roasting.