Lemon Sponge Pie
["1 1/2 Tbsp. butter", "1 c. sugar", "3 Tbsp. flour", "3 eggs, separated", "1 Tbsp. grated lemon rind", "1/3 c. lemon juice", "1 1/2 c. milk"]
["Preheat oven to 425\u00b0.", "Cream butter; stir in flour, sugar and egg yolks.", "Add lemon rind, lemon juice and milk.", "Beat egg whites until stiff.", "Add to egg yolk mixture.", "Pour into unbaked pie shell.", "Bake for 12 minutes at 425\u00b0.", "Reduce heat to 325\u00b0 and bake 30 minutes more.", "Remove from oven and serve."]
["butter", "sugar", "flour", "eggs", "lemon rind", "lemon juice", "milk"]