6 eggs, separated and let stand at room temperature
½ c. milk
1 ½ tbs. honey for glazing
1 tbs. golden syrup
1 ½ tbs. cocoa powder
1 c. vanilla sugar (white sugar stored together with a split vanilla pod in a container for 2 weeks or more)
1 c. plain flour
¼ tsp. salt
A small knob of softened butter for greasing

1. Preheat oven to 340⁰ F / 170⁰ C and boil a pan of water.
2. Brush a square 25 cm cake tin with butter, and then line it completely with parchment.
3. Mix sugar and golden syrup.
4. Sift the dry ingredients minus sugar in another bowl.
5. In a large mixing bowl, beat all egg whites using an electric mixer until foamy.
6. Add the golden syrup mixture and continue whipping the mixture until it becomes glossy.
7. Combine the egg yolks into the mixture one by one, beating well at each insertion.
8. Pour in the dry ingredients and milk in thirds, finishing with an addition of milk.
9. Remove the pan of boiling water from the stove and place the mixing bowl in the pan.
10. Lower the setting of your mixer and keep beating until the mixture is thick enough to coat the back of a spoon (approximately 12 minutes).
11. Bake in the preheated oven for 45 minutes or until a skewer comes out clean when poked into the center of the cake.*
12. Dilute the honey with an equal amount of hot water to glaze the cake top as soon as it comes out of the oven.
13. After a ten-minute cooling session, refrigerate the cake in an airtight container for at least 4 hours so that the castella retains its moist texture.

*Unlike the majority of the cakes, castella hardly rises after baking. Rather than airy, the cake is compound with rich, chewy, almost gelatinous flavor.

“Castella” is Japanese sponge cake originated from Spain, although the sixteenth-century Portuguese missionaries were the ones who introduced it to the Japanese. The sponginess of castella isn’t as feathery-light as that in chiffon cake. Instead, castella is moister, though not as gooey as some cookies. Neither cocoa nor golden syrup was involved in the authentic historical recipe.