5 tbsp. flour
1 c. milk
1/2 c. butter
1 c. sugar
1/2 c. shortening
1 1/2 tsp. vanilla extract

Blend together in saucepan the flour and milk. Cook over low heat until thickened and boiling. Cool to room temperature. Put next 4 ingredients in a bowl and cream together. Beat cooled flour mixture into creamed mixture a tablespoon at a time. When combined beat at high speed until light and fluffy. 12 minutes approximately.