4 egg yolks, beaten
1 cup butter, softened
1/3 cup confectioners' sugar
1 cup white sugar
1/4 cup milk
1 tablespoon lemon extract
In a large bowl, combine egg yolks and butter or margarine. Beat until smooth. In a small bowl, stir together confectioners' sugar and 1 cup of milk. Beat until light in color, or just before baking. Sprinkle egg yolks and 1 cup of milk over thick mixture to create a paste consistency. Stir in 1 tablespoon lemon extract and lemon paste to taste. Chill 5 minutes, then remove from refrigerator.