2 tsp. flour
1/2 c. milk
1/4 c. butter
1/4 c. vegetable shortening
1/2 c. sugar (granulated or powdered)
Dash of salt
1 tsp. vanilla

Mix flour with milk in saucepan. Cook over low heat, stirring constantly until very thick (like paste). Cool. Cream shortening and butter together. Add sugar and beat with electric mixer until light and fluffy. Add the cooled flour mixture and beat about 4 minutes or until thoroughly mixed and icing appears like whipped cream. Add a dash of salt and vanilla to icing. This will generously ice a 2 layer cake.