Butterscotch Filling - cooking recipe

Ingredients

3 tablespoons butter
1 1/2 cups brown sugar
3/4 cup boiling water
3 egg yolks
1 1/2 cups milk
6 tablespoons flour
3/8 teaspoon salt

Preparation

Melt butter.
Add sugar and allow to brown.
Gradually add water.
Beat egg yolks.
Add a small of measured milk and flour.
Stir until smooth.
Add rest of milk and salt. Mix.
Pour this slowly into the sugar mix and cook until thick.
Cool.