Chocolate Custard
["3 c. milk", "3 Tbsp. cocoa", "10 Tbsp. flour", "3 egg yolks", "pie shells, baked", "1 1/2 c. sugar", "1/4 tsp. salt", "2 Tbsp. butter", "1 tsp. vanilla"]
["Mix sugar, flour, eggs, milk and cocoa.", "Cook in top of double boiler over hot water until thick, stirring constantly.", "Cool. Add butter and vanilla.", "Pour into baked pie shells."]
["milk", "cocoa", "flour", "egg yolks", "pie shells", "sugar", "salt", "butter", "vanilla"]