With an electric mixer, beat the eggs and sugar in a bowl until pale and slightly thickened, about 3 minutes.
Add the cheese, lemon zest, vanilla, and salt. Mix on low speed until smooth.
Pour the mixture into a greased 9-inch round cake pan (or flower shaped silicone mold), and bake until the top is golden brown, about 45 minutes. If baked in a pan, run a knife around to loosen.
Let cool completely then turn over onto a serving plate and chill for at least an hour (the colder the better).
Serve topped with whipped cream if desired.
Notes
~ Free Tip ~Substitute sugar with Swerve or another zero calories sweetener that tastes, bakes, and measures like sugar.