Japanese sponge cakes have in general lighter and softer texture than those I find in Australia, and possibly other Western countries. The texture is almost like my Cotton Cheesecake. The most popular sponge cake in Japan is by far the Strawberry Sponge Cake, aka Strawberry Shortcake.
Pre-heat oven to 180°C / 356°F.
Coat the inside of an 18cm / 7" cake tin (note 5) with butter, dust with flour, then shake off the excess flour.
Put the egg yolks in a bowl, add ⅔ of the sugar and beat the egg yolks until they become whitish and thick. Draw a ribbon with the whisk and if the ribbon disappears slowly, it is ready.
In a separate bowl, beat the egg white. When the small bubbles form and the volume of the egg white doubles, add the remaining sugar in 2-3 batches and beat further to make meringue.
When the meringue becomes firm and it can form a peak when you lift the whisk (see the step-by-step photo in the post), it is ready.
Put the flour through the sifter and add to the egg yolk. Fold the batter with a spatula.
Transfer ⅓ of the meringue to the batter and mix with a whisk until the batter becomes smooth.
Pour the melted butter into the batter and fold several times. It's OK even if the butter is not completely mixed.
Pour the batter into the cake tin. Drop the tin onto the work bench to settle the batter in the tin, then, cook in the oven for 25 minutes. Insert a thin bamboo skewer in the centre of the cake to see if the skewer comes out dry. If the skewer is a bit wet, cook further 5 minutes.
Take the tin out of the oven and drop the tin onto the work bench. Remove the cake from the tin and let it cool completely on a rack, upside down (bottom side up).
Put the Syrup ingredients in a small saucepan and bring it to a boil. When the sugar dissolved, turn the heat off.
Whip the cream until soft peak forms. Wipe the strawberries with a wet kitchen paper, remove the stems and halve 10 strawberries.
Leave the sponge cake upside down as is and slice it horizontally in half (note 6), remove the top half and place it next to the bottom half of the cake, cut side up.
Using a brush, coat the cut surface of the two sponge cakes with the syrup gently.
Drop about 3 heaped tablespoons of the whipped cream on the bottom half of the sliced cake and spread it to cover the entire surface. Fill the surface with the halved strawberries, without a gap as much as possible.
Drop about 4 heaped tablespoons of the whipped cream on and spread it to cover the strawberries and the round edge.
Place the top half of the cake on it, syrup side down. Gently press down, making sure the top and bottom cakes are aligned. Fill the gap around the strawberry filling on the side with whipped cream.
(optional) Thinly coat the top and the side of the cake with whipped cream. It is OK not to completely cover the sponge. Leave the cake in the fridge for 10 minutes (note 7).
Using a cake spatula or a long flat spatula, fully cover the top and the side of the cake with the remaining whipped cream, leaving some (about minimum of 4-5 tablespoons) for piping.
Put the remaining cream in a piping bag with a round nozzle. Squeeze out the cream to make a mound of cream in 8 positions around the edge of the surface. Place a strawberry on each mound.
1. My cake is not too sweet. If you prefer it sweeter, increase the quantity of sugar up to 125g / 4.4oz.
2. My 18 strawberries weighed about 450 / 1lb. I used halved strawberries as fillings but if you slice them, you can reduce the number of strawberries.
Instead of strawberries, you can use other berries to make it a mixed berry shortcake (see the photo in the post), or different fruits such as sliced peaches, kiwifruits, pineapples, oranges, grapes, or all of these mixed together!
3. Amount of whipped cream varies depending on the size of the cake tin, how tall your cake is and how much cream you put on the cake.
4. I did not use it but you can add a small amount (½ teaspoon) of liquor of you choice if you want.
5. I tried with a springform cake tin as well as a non-springform tin. The springform tin leaves a dent at the bottom of the cake when cooked so, I prefer a non-springform tin. There is no problem removing the baked cake out of the non-springform tin.
The size of the tin can be up to 21cm / 8". Any larger than that will make the cake thin, and it will not be easy to slice into two layers.
6. The easiest way to slice the round cake horizontally is to make a shallow cut around the side of the cake first, then slide the knife deeper into the centre ensuring that the blade traces the initial cut.
7. This will make the remaining whipped cream stick easier, particularly on the side.
8. My method of making a sponge cake is to beat the egg yolks and whites separately. There is another method of making the batter by beating whole eggs. If you want to use this method, here are the steps to replace the steps 3-9 in my recipe:
1) Put the eggs in a bowl, mix, then add sugar. Beat the eggs over a 60°C / 140°F water bath.
2) When the egg mixture is warmed up to around body temperature, remove the bowl from the water bath.
3) Continue to beat until the egg mixture cools down and becomes thick whitish batter. When you draw a ribbon with the whisk, the trace of the ribbon should slowly disappear.
4) Add the flour through a sifter to the batter and fold it in with a spatula. Add butter and fold several times.
9. You should consume the cake within 2 days. Although the sponge cake will keep longer, the flavour of the strawberries and cream start degrading on 3rd day.
10. Nutrition per serving.
serving: 146g calories: 346kcal fat: 22g (34%) saturated fat: 13g (65%) trans fat: 0.7g polyunsaturated fat: 1.4g monounsaturated fat: 6g cholesterol: 152mg (51%) sodium: 95mg (4%) potassium: 151mg (4%) carbohydrates: 31g (10%) dietary fibre: 1.2g (5%) sugar: 18g protein: 6.2g vitamin a: 18% vitamin c: 40% calcium: 3.8% iron: 7.6%