Buckwheat Sponge Layers
- Pre-heat the oven.
- Rub some butter around the inside of two 18cm/7” round cake tins or insert a cake liner.
- Measure the flour, cocoa and baking powder into a bowl and stir to combine and sieve into another bowl.
- Put the sugar and butter into a mixing bowl or food processor and beat until smooth.
- Break one egg into the bowl and beat until combined.
- Break the second egg into the bowl, add a spoon of the prepared flour and beat again.
- Repeat this with the third and fourth egg. Beat in the vanilla extract.
- Stir in the remaining flour.
- Add the milk and mix again.
- Divide the mixture between the prepared tins and smooth the top.
- Bake for 30-35 minutes.
- Turn the cakes out onto a wire rack and leave to cool.
- Scatter the granulated sugar over the base of a saucepan and sprinkle the water evenly over the sugar.
- Put the saucepan over a medium heat until bubbles start to appear.
- Shake the pan, but do not stir, and leave it to simmer gently until the sugar is fully dissolved.
- Remove the pan of clear syrup from the heat.
- Break the cooked chestnuts into pieces adding them to the hot syrup and stirring so they are fully coated.
- Return the pan to the heat and simmer gently for 1 minutes, shaking the pan occasionally.
- Using a slotted spoon, lift the chestnuts out of the saucepan into a bowl allowing any excess syrup to drain.
- Sprinkle the caster sugar over the chestnuts and stir gently.
- Lift the chestnuts out of the bowl, transferring them to a plate and leave to cool completely.
- Store in an airtight container for up to a week.
White Chocolate Filling
- Break the white chocolate into small pieces.
- Put the chestnut purée and syrup into a saucepan and mix together until smooth.
- Put the pan over a medium heat and when bubbles start to appear, remove the pan from the heat.
- Add the chocolate and leave to stand for 2 minutes.
- Stir until smooth and stand for another 2 minutes to thicken.
- Spread this over one cold cake layer and place the other layer on top.
Chocolate Ganache and Chestnut Topping
- Measure the cream and sugar into the saucepan and stir over medium heat until the sugar has melted and bubbles start to appear.
- Remove the pan from the heat, add the plain chocolate and stand for about 3 minutes while it melts.
- Gently stir everything together.
- Allow to cool, stirring regularly, until the topping starts to thicken a little.
- Spread over the top and sides of the cake.
- Press the frosted chestnuts into the chocolate ganache and leave to set.
- Brush a little edible gold dust onto the chestnuts for decoration.
2 x 18cm/7” round cake tins, 4 x mixing bowls, food processor (optional) and saucepan
180°C, Fan 160°C, 350°F, Gas 4