01 - Preheat oven to 320°F. Line bottom and sides of an 8-inch round cake pan with parchment paper. Wrap exterior of pan with aluminum foil to prevent water seepage during baking.
02 - Set a heatproof bowl over simmering water. Combine cream cheese, butter, and milk in the bowl. Stir until completely smooth and melted. Remove from heat and allow to cool slightly.
03 - Sift together cake flour, cornstarch, and salt. Gradually add dry ingredients to the cream cheese mixture, whisking continuously until fully incorporated and no lumps remain.
04 - Stir in egg yolks, lemon juice, vanilla extract, and lemon zest. Mix until batter is smooth and uniform. Set aside while preparing the meringue.
05 - Using an electric mixer on medium speed, beat egg whites until foamy. Gradually add 3 tbsp sugar in three separate additions, beating after each addition until stiff, glossy peaks form.
06 - Gently fold one-third of the meringue into the cream cheese batter to lighten the mixture. Carefully fold in remaining meringue in two additions, using a rubber spatula with minimal strokes to preserve volume.
07 - Transfer batter to prepared cake pan. Tap pan firmly against counter several times to release trapped air bubbles and settle the mixture evenly.
08 - Place cake pan inside a larger roasting pan. Carefully pour hot water into roasting pan until it reaches halfway up the sides of the cake pan, creating a water bath for gentle baking.
09 - Bake for 60 to 70 minutes until cake is golden brown, set in the center, and a skewer inserted into the middle comes out clean.
10 - Turn off oven and leave cheesecake inside with door slightly ajar for 15 minutes. This gradual cooling helps prevent surface cracking.
11 - Remove from oven and cool completely in the pan. Unmold carefully, then refrigerate for at least 2 hours before serving to allow flavors to develop and texture to set.