Castella Cake

Castella cake, simply referred to as castella, is an impossibly airy and light Japanese sponge sponge cake flavored with honey. It’s humble—never decorated, always loaf-shaped—and so simple. It uses just six ingredients: bread flour, eggs, sugar, honey. and a dash of milk with a pinch of salt. 

Castella cake is super popular in East Asia at large, sold in almost all bakeries that offer variations inspired by European-style breads and baked goods. I only ate it for special occasions growing up–often packed in a super fancy gift box—but now you can make it any day you'd like, in about 1 hour. Despite there being no butter in this recipe, the results are surprisingly rich!

The drama in castella comes from beating the eggs until confidently fluffy, which gives the cake its height and bouncy lightness. Unlike angel food cake, this particular take on castella uses whole eggs rather than just egg whites, so you don't have to worry about separating the yolks out of the picture. There are no other leavening agents like baking powder or baking soda, so the whipping process is super important for the structure of the cake. It will take up to 10 minutes to reach that shiny, ribbon stage and your patience is required! Adding in the sugar gradually will help build a more stable cake mixture. 

Bread flour, which is higher in gluten than all-purpose flour, also contributes to castella’s bouncy texture. If you only have all-purpose flour on hand, you can do a 1:1 substitution, but be sure to follow all our tips below for a smooth baking adventure!

3 Tips to Keep In Mind

1. The eggs must be at room temperature—cold eggs won’t mix as evenly or give you as much volume when beaten. Can’t wait? Drop the cold eggs into a bowl of warm water while you prepare the other ingredients. 
2. Yes, the bread flour should be sifted! If you don’t have a fancy sifter, simply shake it through a wire mesh strainer or whisk it for 30 seconds in a large bowl. Sifting just aerates the flour, which helps lift the castella even more. 
3. Don’t open the oven door. You don’t even have to rotate the pan mid-bake. Use visual cues to check for doneness: the top should be dark brown with a big lift (right over the top of the loaf pan). If opened too soon, the cake may collapse in the middle because of the sudden temperature change. If it happens, no worries! Rest assured, it’s still going to be delicious! 

If you love your fluffy cakes, you might want to check out these angel food cake recipes! 

Editor's note: The introduction to this recipe was updated on May 18, 2022 to include more information.