Melt 3 tablespoons butter or margarine over medium heat.
Stir in 3 or 4 tablespoons flour to roux stage.
Thin roux with milk needed and cooked to desired thickness.
While cooking slowly, stir in more milk and continue to cook slowly (stirring often) until desired thickness attained.
Serve over any flour dessert, hot or cold.
Teaspoon vanilla and spices may be sprinkled on and stirred in sauce.