Cooked Frosting - cooking recipe

Ingredients

3 Tbsp. flour
3/4 c. milk
1/2 c. margarine (1 stick)
2 Tbsp. butter (for flavor)
1/2 c. sugar (granulated)
1 tsp. vanilla

Preparation

Cook flour and milk to a paste, stirring constantly so it doesn't lump.
When it is thick and leaves sides of the pan, set aside to cool (must be cool).