6 medium eggs
For the syrup
175g golden caster sugar
For the kirsch cream
750ml whipping cream
First, make the sponges. Preheat the oven to 180°C, fan 160°C, gas 4. Grease 3 x 22cm-diameter sandwich cake tins and line the bases with baking paper.
In a large bowl, whisk the eggs, vanilla and sugar together using an electric hand whisk until thick and the whisk leaves a trail – it will take about 10 minutes. Sift the cocoa powder and flour together, then fold in. Stir in the melted butter.
Divide the cake mixture between the tins and bake for 20-25 minutes, or until springy to the touch. Cool in the tins for 5 minutes, then turn out on to a rack to cool completely.
Shave the block of chocolate using a potato peeler or by scraping the blade of a kitchen knife across the surface. Chill the shavings.
To make the syrup, put 200ml water and the sugar in a pan; bring to the boil for 5 minutes. Leave to cool; stir in the kirsch. To make the kirsch cream, whip the cream and sugar to firm peaks, then fold in the vanilla and kirsch.
To assemble the cake, level the tops of the sponges using a sharp knife, if necessary. Place a little kirsch cream on a serving plate and secure one of the sponges on top. Brush the sponge with some of the syrup; spread over the raspberry preserve.
Sandwich together with a second sponge and brush again with the syrup. Spread over a layer of the kirsch cream, about 1cm (½in) deep. Cover with the cherries, reserving 8.
Spread a little more cream over the cherries, then top with the final sponge, upside down, to give an even, flat top. Brush with syrup (you may have a little syrup left).
Spoon a quarter of the remaining cream into a piping bag fitted with a large star nozzle; set aside. Using a palette knife, cover the top and sides of the cake with the rest of the cream.
Stick the chocolate shavings over the sides of the cake with your palm. Pipe around the edge of the cake and 8 swirls in the middle; place the reserved cherries on the swirls.