In a small saucepan combine sugar and cornstarch. Stir in water. Stir in egg yolks, lemon peel and lemon juice. Cook and stir over medium heat till bubbly. Cook for two minutes more. Stir in butter till melted. Cover surface with clear plastic wrap; cool. Makes enough to spread between two 8 or 9 in cake layers(about 1 cup).

Microwave directions: In a 1-quart casserole combine sugar and cornstarch. Stir in water. Stir in egg yolks, lemon peel and lemon juice. Micro cook, uncovered, on 100% power(high) for 3 to 4 minutes or till thickened and bubbly, stirring every minute. Cook 30 seconds more. Stir in butter till melted. Cover; cool.

add 1 tablespoon rum after the butter, for a different flavor.