For the matcha sponge you need:
3 tsp matcha (I used Midori Spring ceremonial grade matcha)
2 eggs, separated (size L)
40 g flour
3 tbsp milk
1 tbsp oil
3 tbsp sugar
a pinch of salt
For the sakura mousse you need:
115 g mascarpone
150 g whipped heavy cream
60 g milk
75 g sugar
2 1/2 sheets of gelatin
pink food coloring
150g sakura jam
some pickled sakura flowers
For the sponge, line a round baking pan (20 cm diameter) with parchment paper and grease it. Preheat the oven to 175*C (top and bottom heat).
Whisk together egg yolks, 1 1/2 tbsp of sugar and oil until they have lightened in color.
Now dissolve the matcha in one tbsp of milk until you have a smooth paste, then add the remainig milk and mix thoroughly.
Add this and the flour to the egg yolk mixture and mix again.
Whisk the egg whites until foamy, add the remaining sugar and keep mixing until the mixture is glossy and stiff.
Now carefully fold the egg whites into the matcha and egg yolk mixture until the batter is fluffy and smooth.
Fill the batter into the baking pan and bake for 15 minutes.
Let cool down completely. Remove the sponge from the pan and put it on a plate.
Put the cake ring back around the cake.
For the sakura mousse, soften the gelatin in some cold water. After that, wring out the water as thoroughly as possible. Heat the milk in the microwave for about 45 seconds.
Dissolve the gelatin in the warm milk. Mix mascarpone, sugar and gelatin mix.
Add the whipped cream spoon by spoon to the mix. Now add 100 g of sakura jam and fold into the mixture. Add as much food coloring as you want to achieve your desired color.
Now spread the sakura mousse onto the matcha sponge and make sure you have a smooth and even surface. Then spread the remaining sakura jam as a top layer.
Rinse the sakura blossoms in cold water to remove the salt, let dry a little and place them on the cake.
Refrigerate for at least 3 hours.
Remove the cake ring carefully and enjoy!