• Pre-heat oven to 180°C / 160°C fan assisted / gas mark 4 / 350°F.
• Line and grease 3 x 20cm (8 inch) round cake tins.
• Melt the chocolate in a bain marie or a bowl set over a saucepan of simmering water, then set aside.
• In a large mixing bowl whisk together the flour, sifted cocoa powder, espresso powder, baking powder, bicarbonate of soda and salt until well mixed.
• In a separate bowl mix together the eggs with the sugars.
• Pour in the buttermilk, olive oil, and vanilla then mix until the liquid ingredients are homogenous.
• Pour the liquid ingredients into the flour mixture and whisk until combined.
• Finally mix in the melted chocolate until completely incorporated.
• Divide the mixture between the three cake tins and bake in the oven for 20 minutes until an inserted skewer or cocktail stick comes out clean.
• Turn out the cakes and cool on wire racks before filling and covering with the raspberry crush filling and buttercream.

Raspberry Swiss Meringue Buttercream

• Make the raspberry puree by blending the raspberries together either using an immersion or stand blender.
• Press the puree through a sieve to remove the seeds. Pour the puree into a small saucepan and reduce the puree down by about 50-60% which will take about 5 minutes, stirring occasionally. You want to be left with about 60g of thick jammy raspberry puree. Then set aside to cool whilst you prepare the buttercream.
• Heat the egg whites and caster sugar in a bain marie, or a bowl set over a saucepan of simmering water, stirring constantly until the sugar has dissolved and the temperature has reached 71°C (160°F).
• Remove the egg whites and sugar from the heat and pour into a stand mixer with a whisk attachment. Whisk at low speed until meringue is glossy, forms peaks and has cooled to room temperature. About 68°F to 75°F (20°C to 24°C). This can take 10-15 minutes.
• Change the attachment to a paddle attachment. On a low speed add the butter slowly cube by cube. When you have added all the butter the mixture will look curdled. Do not fret – this is supposed to happen and you just need to carry on mixing the buttercream and waiting it out until it comes together and stabilises into a light creamy consistency. It can take about 10 minutes.
• Pour the raspberry puree into the buttercream along with the vanilla extract and salt and mix in. At first the buttercream will look curdled again but just mix until the buttercream returns to its smooth state. It’s ready for applying to your cake.

Raspberry Crush Filling

• In a medium bowl, crush the raspberries into the jam so the raspberries still have a chunky body.
• Squeeze in the lemon juice and mix to combine.

Assembly

• Place the first chocolate sponge layer on a cake board or plate.
• Pipe a ring of buttercream around the edge of the cake layer which is to hold the raspberry crush filling in place. Spread a thin layer of buttercream in the centre of the cake
• Spoon the raspberry filling into the centre of the cake and spread evenly up to the buttercream dam.
• Place the second chocolate sponge layer directly on top and repeat the process with the buttercream and raspberry filling.
• Place the final chocolate sponge layer on top.
• Apply a thin buttercream layer all over the cake which is called a crumb coat so the chocolate crumbs don’t mix into the final buttercream layer. Chill the cake for 30 minutes to allow the crumb coat to set.
• Apply the final buttercream layer and smooth over the whole cake.
• Arrange the extra raspberries over the top of the cake to decorate.
• You can keep the cake in the fridge until needed but take out of the fridge at least 1 hour before serving so it’s served at room temperature.