Separate the egg yolks from the whites.

In a mixing bowl, whisk the egg yolks until they become smooth and slightly pale.

In a saucepan over medium heat, combine the heavy whipping cream and sweetener (if using).

Heat until the mixture is warm but not boiling, stirring occasionally to dissolve the sweetener.

Slowly pour a small amount of the warm cream into the whisked egg yolks, stirring continuously to prevent curdling.

Gradually add the rest of the cream, continuing to stir until fully combined.

Pour the mixture back into the saucepan and cook over low heat, stirring constantly, until it thickens slightly and coats the back of a spoon.

Do not let it boil to avoid scrambling the eggs.

Remove from heat and stir in the vanilla extract (if using).

Allow the mixture to cool to room temperature.

In a separate bowl, beat the egg whites until they form stiff peaks.

Gently fold the beaten egg whites into the cooled custard mixture until well incorporated.

Pour the mixture into a freezer-safe container.

Cover and freeze for at least 4 hours, stirring every hour to ensure a smooth texture.

Before serving, let the ice cream sit at room temperature for a few minutes to soften.

Scoop into bowls and enjoy.