In a heatproof bowl, whisk together eggs, yolks, sugar, lemon zest, juice, and salt. Place over simmering water and whisk continuously until thickened to a custard consistency. Remove from heat and cool completely.

Beat egg whites until soft peaks form. Gradually add sugar and continue beating until glossy, firm peaks develop.

In a separate bowl, whip heavy cream until firm but smooth peaks form.

Fold egg whites into the cooled lemon base using gentle upward motions. Fold in whipped cream until fully incorporated without deflating the mixture.

Transfer to serving dishes and refrigerate for at least one hour until set.

Top with lightly sweetened whipped cream and optional zest or berries before serving.