Preheat your oven to 300°F (150°C) and prepare an 8-inch cake pan with parchment paper. Set up a water bath.

In a heatproof bowl, combine softened cream cheese, butter, and heavy cream over simmering water, whisk until smooth (about 5 minutes). Stir in egg yolks, cake flour, lemon zest, and vanilla extract.

In a clean bowl, whip separated egg whites with lemon juice; gradually add granulated sugar until medium-soft peaks form (3-5 minutes).

Gently fold one-third of the meringue into the cream cheese batter, then carefully incorporate the remaining meringue in two more additions.

Pour the mixture into the prepared cake pan, smoothing the top, and place it in the water bath. Bake for 80-90 minutes until golden brown.

After baking, turn off the oven and crack the door open, allowing the cheesecake to cool for about 15 minutes before removing it from the water bath.

Chill the cheesecake in the refrigerator for at least one hour before serving.