1 ½cups/150g blackberries fresh or frozenI used frozen
½cup/110g sugar
2tbspwater
1cup/100g blackberriesif frozen defrosted
For the white chocolate buttercream
300g/ 10 oz good quality white chocolatechopped (not chocolate chips)
½cup/125 ml whipping/double cream
½cup/125 g unsalted buttercubed and softened
For the decorations
Chocolate truffles
Maltesers
White sugar pearls
Instructions
For the Cake
Preheat your oven to 350 F/180 C, butter and line 3 8"/20cm cake pans with parchment paper.
Mix together flour, sugar, cocoa, baking powder, baking soda and salt in a large bowl until combined. In a separate bowl mix eggs, milk, oil and vanilla. Add the wet ingredients to the dry ones and beat with an electric mixer until well incorporated.
Divide evenly among 3 pans and bake in the preheated oven for 25 minutes until a toothpick comes out clean. I bake 2 layers together and then the third one later.
Cool in the pans for 10 minutes, then remove cakes from the pans and cool completely on a wire rack.
For the blackberry compote
Combine 1½ cups of blackberries and sugar with water in a small saucepan and cook on low heat until thick and mixture coats the back of a spoon. It will take about 10 minutes.
Remove from heat and process in a food processor or a blender until smooth. Push through a fine sieve to get rid of the seeds. Combine the compote with fresh or defrosted blackberries and set aside.
For the white chocolate buttercream
Heat the cream in a saucepan until it just simmers but not boiling. Take off the heat and pour over chopped white chocolate in a medium sized bowl. Let it sit for a couple of minutes and then stir until chocolate is melted into the cream. Cool for 10 minutes and then start whipping in a stand mixer or with a hand mixer.
Mix for 10 minutes until light and fluffy and is completely cooled, then start adding softened butter by a tablespoon, mix well until entirely incorporated into the frosting after each addition. (You will have enough frosting to fill the cake and ice in the manner of a naked cake.)
To assemble the cake
Load a half of your white chocolate buttercream in a large piping bag with a plain round tip.
Pipe a border around the first layer, it will keep your blackberry compote from leaking out of the sides.
Fill with half of your raspberry compote. Then pipe in the buttercream on top and smooth it out with a spatula.
Top with another layer and repeat the process. Finish with the third layer.
Cover the entire cake with the remaining white chocolate buttercream and then using an offset spatula scrape the mascarpone cream off the sides of the cake to reveal the sponge, thus creating the “naked cake” effect. Decorate the top with chocolate truffles, maltesers and white sugar pearls. Pipe rosettes if desired.