Castella is a Japanese sponge cake commonly eaten throughout the day, but often as part of a late morning snack. It is sweet and generally similar to familiar Western sponge cake except that honey is added to sweeten the cake and is sometimes used as a glaze. This type of cake can be eaten in a restaurant, on the go, or at home. At restaurants, this cake is often served with fresh fruit, fruit preserves, and cream. In Japan, castella is also called kasutera.
The recipe for this sponge cake is basically the same as recipes for the sponge cake served outside Japan, but this cake includes honey and sugar instead of just refined sugar. This cake is made with wheat flour, sugar, and eggs, as well as butter, vanilla, and corn flour. It is often sweetened with honey by gently glazing the cake. The most common way to eat this cake as a single serving is to cut it into small, bite-sized slices.
Though it is highly popular in many parts of Japan, castella is not actually a Japanese invention. This snack originally became popular in Japan because Portuguese traders introduced the sweet snack from their region. The snack was a sponge cake called Pão-de-ló. The foreign snack then became popular in Japan and inspired the creative elaboration on the Japanese sponge cake that led to its current form. Other foods commonly associated with Japan that were actually introduced to Japan by Portuguese visitors include tempura and Japanese winter squash.
Fairly easy to make and easy to work with, castella is a versatile and durable cake that will hold various shapes. It is commonly bought in a rectangular loaf in the packaged baked goods section at grocery stores. In restaurants, castella takes nearly any shape as it is typically cut or shaped in a baking mold. This cake is also frequently found as a street food, and it is commonly served at festivals.
This cake is served differently in different parts of the country. In each area of Japan, restaurants tend to prepare fresh, sweet castella dishes with their own varieties of locally grown fruit. In Okinawa, this is frequently pineapple. Many areas serve castella with strawberries and whipped cream, which is extremely similar to a strawberry shortcake. The similarities mean that the dish is sometimes called strawberry shortcake even when made with castella.