Start by preheating your oven to 350°F (175°C). Grease two 9-inch round cake pans and line the bottoms with parchment paper for easy removal.
In a medium-sized bowl, whisk together the cake flour, baking powder, baking soda, and salt. Set this mixture aside for later use.
In a large mixing bowl, beat the softened butter with an electric mixer until it becomes smooth and creamy. Gradually add the sugar and continue to beat for about 2-3 minutes until light and fluffy.
Slowly add the egg whites, one at a time, to the butter-sugar mixture. Beat well after each addition until fully incorporated. This step helps give the cake its signature light texture.
Add the vanilla extract and almond extract (if using) to the batter, blending until the flavors are evenly distributed.
Begin adding the flour mixture to the batter in three parts, alternating with the milk and sour cream. Start with the dry ingredients, then add some milk, mixing between each addition. Continue until everything is just combined, being careful not to overmix the batter.
Evenly divide the batter between the two prepared pans. Smooth the tops with a spatula and bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean.
Once baked, remove the cakes from the oven and allow them to cool in the pans for about 10 minutes. Afterward, transfer them to a wire rack to cool completely before frosting or serving.
You can use your favorite frosting—whether it’s a buttercream, cream cheese frosting, or a simple whipped cream—to finish your white cake. Decorate with fresh fruits, sprinkles, or serve as is for a classic look.