The Castella cake is a light sponge cake popular in Japan and seems to be sold often as a plain bar cake. It is classified as a kind of ‘wagashi‘ or Japanese traditional confectionery, according to Wikipedia.
I found a recipe on Youtube that seemed simple enough and flavoured with orange juice and zest for a unique touch.
Of course, with such a simple palate to work with, adding garnishes like fruits and berries and sauces seems obvious. The cake itself is only slightly sweetened. This plating used fresh raspberries and raspberry coulis combining the tartness of the fresh berries with the sweet raspberry sauce.
The recipe was transcribed from the ingredients given in the Youtube video and the instructions described what I actually did to achieve the results above.
Orange Cotton Sponge Cake/Castella Cake – 18 cm x 18 cm x 6 cm/8 inch square glass pan, ended up 4 cm/1 1/4 inches tall after cooling and some shrinking
Egg Yolk Mixture
5 egg yolks
1 whole egg
50 ml/3 tbsp + 1 tsp vegetable oil
65 ml orange juice
2-3 tbsp orange zest
75 gm cake flour**
Egg White Mixture
5 egg whites
60 gm caster sugar (try increasing sugar to 90-100 gm)
1/4 tsp lemon juice
** I didn’t have any cake flour so I substituted it with 60 gm all purpose flour (Canadian Red Roses, 13% protein) and 15 gm cornstarch sifted together.
Oil the glass pan and line it carefully with two cross-wise strips of parchment paper.
In a large bowl, whisk together the 5 egg yolks and the whole egg. Add the vegetable oil. Whisk in the orange juice. Add the zest.
Sift in the cake flour. Whisk in gently until you have a homogeneous mixture.
In a large bowl whisk the egg whites until foamy. Add the lemon juice and sugar and beat until you have stiff peaks. Fold in about 1/3 of the egg whites to lighten the egg yolk mixture. Add the rest of the whites and gently fold in.
Preheat the oven to 140 deg C/285 deg F.
Smooth the surface using an off-set spatula. Place the pan into a larger pan for a water bath and fill with water about 3 cm/1 inch deep.
Bake 70-80 min. Test for doneness by inserting a toothpick into the center of the cake. If it comes out clean and dry, the cake is done.
Remove the pan from the oven and then the cake pan from water bath. Bang the pan firmly on the counter (to set the cake??).
Let the cake pan rest for 5-10 minutes on a cooling rack before removing the cake from the cake pan. Peel off the parchment paper. Let cool to room temperature before cutting.