My Grandma's Heavenly Frosting

This frosting is called heavenly frosting for a reason.  It's amazing!!  It's my Grandma's old recipe and I think of her every time I make it.  It is meant to top Red Velvet Cake and that combination is unbelievable, but I've used the frosting for other cakes as well.  Just try it, you will be in "HEAVEN"!  This is coming from someone who normally scrapes frosting off of cakes and cookies, but this I could eat with a spoon.

5 Tablespoons flour
1 Cup milk
1 Cup sugar
1 Cup butter
1 teaspoon vanilla

1. Cook flour and milk in a saucepan stirring constantly until really thick.  Let cool.
2. Cream sugar, butter and vanilla together with an electric mixer.
3. After flour mixture has cooled, add to butter/sugar mixture and beat on high speed until it is the consistency of whipped cream.
4. Spread on cake and be sure to lick the bowl and beaters!