Preheat Oven:

• Preheat your oven to 320°F (160°C). Line a 12-cup muffin tin with cupcake liners or grease and flour the cups.

Prepare the Cream Cheese Mixture:

• In a medium saucepan, combine the cream cheese, butter, and whole milk.

• Heat over low to medium heat, stirring occasionally, until the cream cheese and butter are completely melted and smooth. Remove from the heat and let it cool to room temperature.

Mix Dry Ingredients:

• In a separate bowl, whisk together the all-purpose flour, cornstarch, and salt. Set aside.

Egg Yolks:

• In a large bowl, whisk together the egg yolks, granulated sugar, and lemon juice (if using) until the mixture is smooth and pale.

• Slowly pour in the cooled cream cheese mixture, whisking continuously to combine.

Add Dry Ingredients:

• Gradually sift in the flour mixture into the egg yolk mixture, mixing gently until fully combined. Set the batter aside.

Whip Egg Whites:

• In a separate, clean bowl, beat the egg whites with a handheld mixer or stand mixer on medium-high speed until soft peaks form.

• Gradually add 2 tablespoons of granulated sugar and continue to beat until stiff peaks form (the egg whites should stand up firmly when the beaters are lifted).

Combine the Mixtures:

• Gently fold a third of the whipped egg whites into the batter to lighten it, using a spatula and careful folding motions.

• Once the mixture is lightened, fold in the remaining egg whites, being careful not to deflate the batter.

Bake:

• Pour the batter evenly into the prepared muffin cups, filling each about 3/4 of the way full.

• Tap the muffin tin gently on the counter to release any air bubbles.

• Place the muffin tin into the oven and bake for 20-25 minutes, or until the tops are golden brown and slightly puffed.

• Note: The cupcakes will continue to rise and may collapse slightly as they cool, which is normal for Japanese cotton cheesecakes.

Cool:

• Allow the cupcakes to cool in the tin for 5 minutes before transferring them to a wire rack to cool completely.

• The cupcakes will shrink a bit as they cool, but they should remain soft and fluffy.

Serve:

• Once cooled, dust the tops with powdered sugar if desired, and serve. These cupcakes are best enjoyed the same day but can be stored in an airtight container in the refrigerator for up to 2-3 days.