Preheat oven to 320°F (160°C). Grease and line a springform pan.
In a bowl, beat the cream cheese until smooth. Add butter and mix until combined.
Gradually add milk, mixing until smooth. Sift in cake flour and cornstarch, and mix well.
Add egg yolks, sugar, lemon juice, and mix until smooth.
In a separate bowl, beat egg whites with cream of tartar until stiff peaks form.
Fold the egg whites into the cream cheese mixture in three additions.
Pour the batter into the prepared pan. Place the pan in a larger baking dish filled with hot water (water bath).
Bake for 60 minutes or until the top is golden brown and a skewer inserted into the center comes out clean.
Turn off the oven and leave the cheesecake inside with the door slightly open for 15 minutes.
Remove from oven and cool completely before removing from the pan. Refrigerate before serving.