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An incredibly soft, smooth, rich, velvety chocolate castella cake, perfectly light with a springy texture are some of the characteristics of Taiwan castella cake that will leave you craving for more.
Known for its incredible softness and airiness, Taiwanese castella cake sure has gained immense popularity worldwide. A few years ago, I bake this Taiwanese pandan castella cake and this cream cheese castella cake and I never looked back. I wrote a bit more about what castella cake is and its origin here. The Taiwanese castella cake collection is simply not complete without the chocolate version 🙂
Taiwanese Chocolate Castella Cake
Ingredients
Cake batter:
- 100 g egg yolks from 5 large eggs
- 55 g unsalted butter
- 75 g whole milk
- 40 g cake flour
- 25 g cocoa powder
- ¼ tsp salt
- 30 g semi-sweet chocolate chips or milk/dark chocolate
Meringue:
- 150 g egg whites from 5 large eggs
- 80 g granulated sugar
- 1 tsp lemon juice or vinegar
Topping:
- Mini chocolate chips
Instructions
Things to prepare before you get started:
- Preheat oven to 300 F (150 C) for conventional oven. If you use convection oven, lower the temperature by 20 degrees. Get the eggs out from the fridge and separate the whites from the yolks into separate mixing bowl. They are easier to separate when cold. Let them come to a room temperature.
- We will bake the cake in a water bath. Get another larger pan and fill it up with water, about 1/2 inch full and put it inside the oven, on the middle rack. So the water will heat up together with the oven
- I use 7-inch round pan with a loose-bottom piece. Line your cake pan with parchment paper on the bottom and the sides. If you use a loose-bottom pan like me, put the pan inside another pan. I found that water still manages to sip in when I double wrapping with aluminum foil
Prepare the cake batter:
- Combine the cake flour, cocoa powder, and salt. Set aside
Set up a double boiler (bain marie):
- Put some water in a saucepan and set a heat-proof bowl sitting on top of the saucepan. The water shouldn't be touching the bottom of the bowl
- Add butter and milk to the double boiler you set up and whisk until the butter melts. Add the chocolate and whisk until melt. Do not overheat. Remove from the heat and wipe the bottom of the bowl
- Add the yolks and whisk to combine. Whisk in the flour mixture and use a whisk to combine again
Prepare the egg white meringue:
- Beat egg whites on low speed until foamy, then add vinegar and continue beating for another minute and then increase the speed to medium (speed 6 on KA) and add sugar in 3-4 batches and continue to beat until you get a medium-soft peak. When you lift the meringue up with a whisk, the tail will bent. Do not overwhip the meringue
Fold the meringue into the cake batter:
- Add 1/3 of the meringue into the cake batter. Use a whisk to swipe down and fold over to combine and then continue with the next 1/3 of meringue. After adding the last 1/3 of meringue, switch to spatula and then swipe down and fold over to combine until you no longer see the white meringue. Try to work fast and not to overfold the meringue and deflate it
- Pour the batter into the prepared pan. Bang the cake pan on the countertop a few times to pop large air bubbles. Place the cake pan inside the larger pan. Decorate the top very gently with some mini chocolate chips
Bake the cake:
- Very carefully transfer the cake pan and put it inside the larger pan with water that you prepared earlier. Bake for the next 1 hour 50 minutes to 2 hours. Took me 2 hours with my oven. You can start checking on the cake at about 1 hour 30 minutes mark. The cake should bounce back when you gently touch it. It should be dry to touch. A cake tester should come out clean with maybe a few crumbs but it shouldn't be wet
Cooling down:
- Remove from the oven and immediately and bang on the countertop a few times to minimize shrinkage. Then push the cake out of the pan. Place on a cooling rack and gently peel off the parchment paper on the side of the cake and let it cools down completely this way before cutting. The cake will jiggle when you pat on it. It will stop jiggling once the cake has cooled down completely
Serve:
- Use a serrated knife to cut the cake so you won't squish down the cotton soft cake. The castella cake can be kept in room temperature for 3 days in an air-tight container
RECOMMEDED TOOLS
*Nutrition facts are just estimates and calculated using online tools*
How to bake Taiwanese chocolate castella cake
1. We will bake the cake in a water bath. Get another larger pan and fill it up with water, about 1/2 inch full and put it inside the oven, on the middle rack. So the water will heat up together with the oven
2. Line your cake pan with parchment paper on the bottom and the sides. If you use a loose-bottom pan like me, put the pan inside another pan. I found that water still manages to sip in when I double wrapping with aluminum foil
3. Combine the cake flour, cocoa powder, and salt. Set aside. Put some water in a saucepan and set a heat-proof bowl sitting on top of the saucepan. The water shouldn’t be touching the bottom of the bowl. Add butter and milk to the double boiler you set up and whisk until the butter melts.
4. Add the chocolate and whisk until it melts. Do not overheat. Remove from the heat and wipe the bottom of the bowl. Add the yolks and whisk to combine. 
5. Whisk in the flour mixture and use a whisk to combine again
6. Beat egg whites on low speed until foamy, then add vinegar and continue beating for another minute and then increase the speed to medium (speed 6 on KA) and add sugar in 3-4 batches and continue to beat until you get a medium-soft peak. When you lift the meringue up with a whisk, the tail will bent. Do not overwhip the meringue
7. Add 1/3 of the meringue into the cake batter. Use a whisk to swipe down and fold over to combine and then continue with the next 1/3 of meringue. 
8. After adding the last 1/3 of meringue, switch to spatula and then swipe down and fold over to combine until you no longer see the white meringue. Try to work fast and not to overfold the meringue and deflate it
9. Pour the batter into the prepared pan. Bang the cake pan on the countertop a few times to pop large air bubbles. Use a skewer to draw circles or zigzag to pop air bubbles inside the batter. 
10. Place the cake pan inside the larger pan. Decorate the top very gently with some mini chocolate chips
11. Very carefully transfer the cake pan and put it inside the larger pan with water that you prepared earlier. Bake for the next 1 hour 50 minutes to 2 hours. Took me 2 hours with my oven. 
12. You can start checking on the cake at about 1 hour 30 minutes mark. The cake should bounce back when you gently touch it. It should be dry to touch. A cake tester should come out clean with maybe a few crumbs but it shouldn’t be wet
13. Remove from the oven and immediately and bang on the countertop a few times to minimize shrinkage. 
14. Then push the cake out of the pan. Place on a cooling rack and gently peel off the parchment paper on the side of the cake and let it cools down completely this way before cutting. The cake will jiggle when you pat on it. It will stop jiggling once the cake has cooled down completely
15. Use a serrated knife to cut the cake so you won’t squish down the cotton soft cake. The castella cake can be kept in room temperature for 3 days in an air-tight container
Important tips
1. Make sure ingredients are at room temperature, especially the eggs
2. Do not overwhip meringue. We want a medium-soft peak, the tail bends when you lift up the whisk
3. If you use a loose-bottom pan, be sure to put it in another larger pan to prevent water from sipping through the cracks
4. Bake at low temperature and slowly. This is to ensure your cake won’t deflate when you take it out of the oven
Did you make this recipe?
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2 comments
Hello.
Thank you for the lovely recipe.
May I know what is the size of the cake pan used for this cake pls.
Thank you.
Hi Farhana, I used 7-inch round pan with loose-bottom piece.