Perfect Caramel Icing
["1 stick margarine", "1 c. brown sugar", "1/4 c. milk", "2 c. powdered sugar"]
["Melt margarine and brown sugar.", "Cook 2 minutes; add 1/4 cup milk.", "Let come to a boil.", "Cool and add powdered sugar."]
["margarine", "brown sugar", "milk", "powdered sugar"]