I decided on matcha castella as the snack to bring to a party, and it was an amazing decision. Matcha castella is a sponge cake flavored with green tea powder often referred to as “matcha”. At the grocery market prior to making these gorgeous green beauties. These were spongy, soft, moist, and had a light flavor of green tea. I was surprised they didn’t have that egg taste that some baked goods tend to have when there are so many eggs (there are 5 whole eggs used for these ones!).
The recipe I used is this one by Roti n Rice which also calls for a Japanese alcoholic drink usually used for cooking called “mirin” – which I also don’t normally have on hand. However, this one is completely optional so I simply left it out.
I tried to find bread flour which is said to be one of the key ingredients to making castellas. However, I was only able to find those huge bags of bread flour which would be unsuitable for me since I would be moving away for university and no one in my house bakes! After a bit of research online for “bread flour substitution” and the like, it turns out that there’s no real substitution since bread flour naturally has the proteins that keep the batter stretchy and spongy. However, I came across this one comment by someone called “Ruby” who said that what mattered most was making the eggs warm before beating.
So put all five eggs into a little pot of water and let the water heat up until warm. The eggs were warm to touch, and you can tell that they haven’t hardened on the inside yet by shaking it to hear the sound of the egg sloshing around. I would have to say this has to be the key that made all-purpose flour okay for this castella!
I tried beating the egg whites with a fork at first until I realized I had an electronic hand mixer (beating with a fork would probably take forever by the way!). It was a breeze from then. You really do have to beat the egg whites and sugar for a full five minutes in order to achieve those white peaks though! No skimping on time there.
I beat the egg yolks in one at a time as instructed, then added my matcha + all-purpose flour mixture. It bothered me that the matcha made the batter spotted in green flecks, but this is luckily not noticeable in the finished castella! As you can see, I am not so great at lining the 8×8 pan with aluminum foil. This is okay though since you cut off the 4 edges after cooling in the fridge overnight – I snacked on mine after cutting.
After baking, cooling, wrapping and refrigerating as the recipe instructs, this is the big slab of matcha castella I got after cutting the 4 edges. During baking, I was worried because it seemed like bubbles were forming at the top from the heat, but these didn’t form giant meteor-like holes of my baking nightmares.
I cut the slab into quarters, then each quarter into halves, then finally each half into thirds! This formed 36 pieces of party-perfect, snacking-sized matcha castella pieces 🙂 Enjoy~