4 egg yolks
3/4 c. sugar
1/4 c. lemon juice, plus 1 tsp. grated lemon rind
1 tbsp. butter
2 egg whites
1 baked pie shell

Cream together sugar and lightly beaten egg yolks. Add lemon juice and rind. Cook over low heat while stirring until thickened, and add butter. Remove from heat, and fold in the stiffly beaten egg whites when cool, then pour into baked pie shell.