Sweet lemon butter

Ingredients:

1/2 cup butter
Grated peel of 1 lemon
1/2 cup freshly-squeezed lemon juice
1 1/2 cups granulated sugar
1/4 teaspoon salt
3 whole eggs
3 egg yolks

Preparation:

Melt butter in top of double boiler.
Stir in lemon peel, juice, sugar and salt.
Lightly beat whole eggs into egg yolks.
Blend eggs into sugar mixture.
Cook over boiling water, beating with whisk until thick and smooth, about 20 minutes.
Cover and store in refrigerator.