I have recreated this recipe from: https://chefstallorder.blogspot.com/2017/06/matcha-tea-chocolate-sponge-cake.html
300 g softened unsalted butter
300 g caster sugar
300 g self-raising
90 g cocoa powder
20 g matcha powder, extra for sprinkling on the custard (a pinch)
100-150 ml thick pouring custard
1 1/2 Tsp baking powder
Preheat 180 Deg C. For the sponges, cream together the butter and the sugar. When light, gradually add the eggs, followed by the flour and baking powder. Separate the cake batter into 2 bowls. In the first, beat in the cocoa powder, then matcha into the other half.
Spoon half chocolate on one side and matcha on the other into 23 cm lined tin with baking paper. With the beater using hand, give the batters a good mix for the marble effect. Then pour thick custard on top and sprinkle some matcha onto custard.
Then spoon the remaining chocolate and matcha over the custard and smooth the top using the same spoon you spoon the chocolate for the matcha; in this way you have a mixture of choclate and matcha.
Bake in a pre-heated oven at 180 degrees for 55 – 75 minutes. (Oven dependent). Check with a skewer that they are cooked before removing.
Switch off oven and leave to cool for 10 minutes in the tin and in oven before, removing from oven and tin, then cooling on a wire rack. After about 25 minutes transfer to serving plate.
Note: You can make the butter cream. I did not make the butter cream.
250g softened butter
500g icing sugar
3g matcha tea powder
20g cocoa powder
2 tbsp milk
For the buttercream, beat the softened butter until pale and light. Sift in half the icing sugar and beat well, sift in the rest and mix thoroughly. Add the milk to loosen the buttercream. (Add more if required).
Split the buttercream in half. Beat the sifted matcha tea powder into one, sifted cocoa powder into the other.
For the building, once the sponges are cold it’s time to build. Healthily cover the top of one with matcha buttercream. Add a layer of sponge and cover with chocolate buttercream. Top off with the last sponge.
Spoon all remaining matcha buttercream on top the top of the cake. Smooth over the top and roughly do the sides. With a little chocolate buttercream, you’re looking to give a 2-3cm rim of frosting at the top. If you can try and work the 2 butter creams together so it’s not a harsh transition. Don’t worry if it’s not perfect it’s not meant to be.
With any remaining buttercream, decorate as you please.