Fluffy and Moist Chocolate Sponge Cake

Fluffy and Moist Chocolate Sponge Cake

This is a fluffy sponge cake made with pure cocoa powder. I added mizuame starch syrup to the batter and obtained a light and moist Genoise style chocolate sponge with a dense chocolate flavor.

Ingredients: For a 18 cm round cake tin

Cake flour
80 g
10 g
Egg (beaten)
30 g (1/2 of beaten egg)
Granulated sugar
80 g
Mizuame starch syrup (refer to the Steps 28 - 29
30 g
60 g
☆Vegetable oil
20 g
☆Unsalted butter
15 g
Pure cocoa powder
20 g
Vanilla oil
a few drops


1. Prepare the cake tin. Grease the tin with oil thinly and line with baking parchment. I cut a piece of parchment paper into a round shape to fit it in. Measure the ingredients.
2. Put the ☆ ingredients into a heat-proof dish and warm them up. Add the pure cocoa powder and mix well. To keep hot, place the dish over a bain-marie or on top of the oven while it's preheating.
3. Preheat the oven to 170°C. I usually start to preheat the oven while I whisk the eggs.
4. Beat 3 eggs and 1/2 and add the sugar in 3 batches. Continue to beat until fluffy. Add the mizuame starch syrup (or honey) to the mixture.
5. Beat until the mixture forms a thick ribbon when the hand mixer is lifted. Lower the hand mixer speed to low and beat the mixture for 3 to 5 minutes to make its texture silky-smooth.
6. Beat constantly until the mixture forms a thin ribbon that disappears slowly when the mixer is lifted. The texture must be very smooth and delicate.
7. Sift the cake flour and cornstarch together through a fine sieve. Whisk the flour mixture in the sieve with a whisk.
8. Sift 1/2 of the Step 7 flour mixture into Step 6 and mix gently with a spatula. When the flour is evenly combined, add the rest of the flour mixture.
9. Fold in the mixture with a spatula gently until no longer lumpy. Add a few drops of vanilla oil.
10. Fold in until the flour is combined well. Add the ☆ cocoa liquid in 3 or 4 batches. Pour the liquid onto a spatula first and drizzle over the liquid overall. Stir well quickly.
11. Fold in the mixture by scooping up from the bottom in a circular motion from various positions until the cocoa liquid is well combined.
12. Pour the batter into the prepared cake tin from a high point. Do not scrape the batter on the sides of the bowl with a spatula, but tilt the bowl to pour the batter.
13. The batter left on the sides of the bowl tends to contain more fat, so it is better not to put it into the cake tin. If you want to put it in, pour it along the sides of the cake tin.
14. Give several sharp taps to the cake tin to remove the excess air. Pop the bubbles on the surface with a toothpick and put the tin into the oven quickly.
15. Lower the oven temperature to 160°C and bake for about 35 minutes. When you press the centre of the batter with your finger and it springs back, it is done. If it sinks, continue to bake.
16. If you want to be sure, use a skewer. When an inserted skewer in the centre comes out clean, it is done. Adjust the baking time according to your oven at home.
17. The baking time affects the result. If the cake is removed from the oven too early it might collapse. It is important to se as it goes.
18. Do not overcook either. Overcooking may harden the edges or dry the sponge.
19. After removing the tin from the oven, drop the cake tin from about 30 cm to get rid of the excess steam. The sponge will settle down to the same height as the sides of the cake tin.
20. Remove the sponge from the tin and peel off the baking parchment gently.
21. Cover the sponge with a moistened tea towel and leave to cool. After completely cooled, remove the tea towel and wrap the sponge with cling film or a plastic bag.
22. Unfortunately, this sponge has a crack on the surface. When I mixed with the hand mixer, it was so fast that I mixed the eggs too long, which might cause this.
23. I sliced the sponge into 3 pieces horizontally.
24. The next day I drizzled with syrup to make a coffee-mocha decoration cake - Recipe ID: 1215091.
25. Chocolate cream decoration - Recipe ID: 1206577.

Story Behind this Recipe

I arranged my fluffy and soft plain sponge cake to make this chocolate sponge. I added honey and starch syrup, and adjusted the amount of fat so as to make a fluffy and moist, but not dry sponge cake.