2 tbsp. flour
Pinch of salt
1/2 c. confectionery sugar
1/2 c. milk
1/2 c. butter
1 tsp. vanilla

Cook flour, milk and salt until thick, stirring constantly. Cool, cover while cooling to avoid a dry top.

Beat butter. Add confectionery sugar a little at a time, beating well. Add cooled flour mixture and vanilla. Beat well.