ICING:

1 1/2 c. sugar
1/3 c. corn starch
1 1/4 c. water
1 lg. egg yolk
4 oz. cream cheese
1/4 c. lemon juice
1/4 c. butter
1 tbsp. lemon rind

CAKE:

1 box Duncan Hines cake mix
4 eggs
1/2 c. milk
1 stick butter
1 tbsp. lemon juice

Bake cake according to instructions. Cool.

Icing: Cook sugar, water, corn starch until thickens. Gradually stir in egg yolks, stirring fast until it boils again, about 1 minute.

Blend in butter, lemon juice, rind, and softened cream cheese. Remove from heat and beat with mixer. Spread while hot on cake.