Separate the egg whites from the yolks and whip the egg whites until soft peaks form, then gradually add granulated sugar until stiff peaks form.

In another bowl, combine egg yolks, fresh lemon juice, and zest; cook over a double boiler for 5-7 minutes until thickened.

Allow the egg yolk mixture to cool slightly, then fold in the cold heavy whipping cream until well combined.

Gently fold in the whipped egg whites in batches to maintain airiness.

Transfer to serving glasses and chill for at least 4 hours until set.

Serve chilled with additional whipped cream, lemon zest, or berries as garnish.