In top of double boiler, combine eggs, egg yolks
and sugar; mix well. Add lemon peel, lemon juice and butter.
Cook over gently boiling water, stirring frequently,
until the mixture is smooth and thickened.
Remove from heat at once, and let cool.

To store: turn into glass jars or plastic freezer containers.
To keep for several days, store in refrigerator, tightly covered.
If keeping for several weeks, store in freezer. Before using,
let stand at room temperature several hours to thaw.
Makes a delicious filling for tarts or a spread for toast.
Makes 2 pints.