Preheat your oven to 320°F (160°C).

Grease a 9-inch round cake pan and line the bottom with parchment paper.

In a large bowl, beat the softened cream cheese until smooth.

Gradually add the granulated sugar, mixing until fluffy.

Pour in the milk and melted butter, mixing well to combine.

Add the egg yolks one at a time, ensuring each is fully mixed before the next.

Sift in the cake flour and cornstarch, then add the vanilla extract.

Mix until fully combined, careful not to over-mix.

In a separate bowl, beat the egg whites with cream of tartar until soft peaks form.

Gradually add the remaining sugar and keep mixing until stiff peaks form.

Gently fold the whipped egg whites into the cream cheese mixture in three parts.

Pour the batter into the prepared cake pan.

Place your cake pan in a larger baking pan filled with hot water.

Bake for about 60 minutes, or until the top is lightly browned and a toothpick comes out clean.

Turn off the oven and let the cake cool in the oven with the door slightly ajar for about an hour.

Remove the cake from the oven and let it cool to room temperature before refrigerating for at least four hours.

Slice, serve, and enjoy the fluffy and airy texture of your homemade Japanese Cheesecake.