Japanese sponge cake, also known as Castella cake, is a very soft cake that, unlike our sponge cake, does not need to be soaked because it remains very moist and soft. The original recipe calls for flavoring it with a Japanese liqueur, but not having it, I opted for vanilla extract, but citrus zest will also work perfectly! Making it is very simple and quick, and the result is delicious. Let’s get to work and prepare the Castella cake together.
If you are looking for other delicious desserts, here are some great ideas.

- Difficulty: Easy
- Cost: Cheap
- Preparation time: 10 Minutes
- Portions: 8
- Cooking methods: Oven
- Cuisine: Japanese
- Seasonality: All seasons
Ingredients for preparing Castella cake
- 4 eggs
- 1/2 cup all-purpose flour
- 1/4 cup butter
- 1/3 cup sugar
- 1/4 cup milk
- 1 teaspoon vanilla extract
- 1 pinch salt
Tools
This post contains affiliate links
- Electric whisks
- Baking pan 8×10
Steps for preparing Castella cake
In a small saucepan, heat the milk, add the butter and vanilla extract, and stir until the mixture is smooth. Pour it over the sifted flour, add a pinch of salt, and mix well.
Add one egg yolk at a time, working with a hand whisk. Meanwhile, beat the egg whites with an electric whisk until stiff peaks form as you gradually pour in the sugar. Fold the egg whites into the previously prepared mixture, mixing from bottom to top to avoid deflating them.
Pour the mixture into a baking pan lined with parchment paper. Place the pan inside a larger pan and add at least a couple of inches of water (bake in a water bath in the oven). Place the pans in a preheated oven at 320°F, static, for about an hour; do the toothpick test anyway. Remove from oven, let cool, and after unmolding, cut into slices or cubes.
Storage
The cake keeps for a couple of days under a glass dome.