Mix
½ c shortening
¼ c butter, 3/4 c sugar
1 tsp vanilla
Beat until light and fluffy. Then mix
3-1/2 tbls flour with
¾ c milk
Mix as for white sauce, and cook until thickened. Add by tablespoonfuls to first mixture, beating after each addition until creamy and light as whipped cream.
May be stored in the refrigerator for future use. It will soften up after sitting out for a while.