Preheat your oven to 350°F (175°C). Grease two 9-inch round cake pans with butter or non-stick spray.

In a large mixing bowl, whisk together the cake flour, granulated sugar, and baking powder until well combined.

Whip the egg whites in a clean, dry mixing bowl until stiff peaks form, about 3-5 minutes.

Combine the whole milk, melted unsalted butter, and pure vanilla extract in another bowl, then mix until smooth.

Gradually add the wet ingredients to the dry ingredients, stirring gently until just combined.

Fold the whipped egg whites into the batter gently, ensuring you maintain airiness.

Pour the batter into prepared pans and bake for 25-30 minutes, or until the tops are golden and a toothpick comes out clean.

Let the cakes cool in the pans for 10 minutes, then turn them out onto a wire rack to cool completely.

Once cool, frost with your favorite frosting or serve plain with a dusting of powdered sugar.