Lemon Sponge Pie
["1/4 c. melted butter", "1 c. sugar", "3 Tbsp. flour", "3 slightly beaten egg yolks", "juice and grated peel of 1 lemon", "1 1/2 c. milk", "3 stiffly beaten egg whites"]
["Blend butter with sugar and flour; add egg yolks, lemon juice, lemon peel and milk.", "Mix well.", "Fold in egg whites.", "Pour into 9-inch unbaked pastry shell.", "Bake at 450\u00b0 for 8 minutes, then at 325\u00b0 for 25 minutes, plus turn off oven and leave pie inside 20 minutes."]
["butter", "sugar", "flour", "egg yolks", "lemon", "milk", "egg whites"]