Lemon Butter Tarts 
Makes 12 small tarts 

1/2 cup butter or margarine
2 teaspoons grated lemon rind
1/3 cup lemon juice
1 1/2 cups white sugar
3 eggs
2 egg yolks
12 -3 inch baked tart shells
3 egg whites
1/4 cup white sugar
                   
1. Melt butter in a saucepan. Add rind, lemon juice, and 1 1/2 cups
   sugar. Beat eggs and egg yolks until thick, and add to lemon
   butter mixture. Cook over low heat, stirring constantly until
   thick. Chill. 
2. Beat 3 egg whites until stiff. Gradually add 1/4 cup sugar, and
   continue beating until stiff and glossy. Fill baked tart shells
   with lemon custard, and top with merange Bake at 350 degrees F 
   just until tarts are a delicate brown color.