Mom'S Butterscotch Pie Filling - cooking recipe

Ingredients

4 Tbsp. flour (level)
2 Tbsp. butter
1 c. brown sugar
1 1/2 c. milk
1 tsp. vanilla
2 egg yolks

Preparation

Mix all dry ingredients; put into saucepan that has the beaten egg yolks and milk.
Cook until thick and add vanilla.
Enough filling for one large pie.