Chocolate Pie - cooking recipe

Ingredients

1 c. sugar
3 Tbsp. cocoa
3 Tbsp. flour
pinch of salt
3 eggs, separated
2 1/4 c. milk

Preparation

Mix cocoa, sugar, flour and milk in top of double boiler. When it begins to thicken, add to beaten egg yolks, then return all to double boiler.
Stir constantly until thick.
Remove from heat and add 2 tablespoons butter.
Stir, cool and add vanilla. Pour into cooked pie shell.