Perfect Sponge Cake for Filling Cakes or Eating Plain

Beat the egg whites in a stand mixer until stiff peaks form and set aside.

In the same mixer, add the egg yolks and water, beating until the mixture doubles in volume.

Add the sugar and salt to the egg yolk mixture and beat quickly for about one minute.

Add the sifted all-purpose flour. Scrape down the sides of the bowl if necessary, and mix gently.

Gently fold in the baking powder and the stiff egg whites, mixing very lightly on the low speed of the mixer just to combine.

Finish mixing manually with a fork or spatula, ensuring all ingredients are incorporated smoothly.

Pour the batter into a square pan (the shape is optional) that has been greased and lined as you usually prepare it.

Bake in a preheated oven at 200°C (approximately 400°F) for about 35 to 40 minutes. Do not open the oven during the process.

As soon as you remove it from the oven, immediately turn the sponge cake out of the pan, as it may deflate if it cools inside.