1 tsp. rum
1/4 c. margarine
1/4 c. whole milk
1/4 tsp. salt
3 1/2 c. confectioners sugar (sifted)
In a large mixing bowl, cream butter until light and fluffy. Add rum, milk and mix until well blended. Gradually add sugar, vigorously stirring after each addition until frosting reaches the proper consistency for spreading. It should be thick enough to hold its shape when a spoonful is place on cake.