Servings 12 slices
- 220 g plain flour
- 400 g caster sugar
- 90 g cocoa powder
- 2 tsp baking soda
- 1 tsp baking powder
- 1 tsp salt
- 225 g buttermilk
- 120 g vegetable oil
- 2 eggs large
- 1 tsp vanilla extract
- 230 g coffee
- 250 g unsalted butter
- 180 g icing sugar
- 2 tbsp coffee strong, or espresso
- 1 tsp vanilla extract
- 55 g cocoa powder
- 100 g dark chocolate
- chopped walnuts to decorate, optional
- Preheat the oven to 180 c/ 350 F. Line 2 x 22-23cms (8-inch) springform cake tins with baking paper (bottom and sides). Lightly spray the paper with cooking spray.
- Sift the flour, cocoa, baking soda and powder and salt into the bowl of your stand mixer fitted with a paddle attachment. Then add the sugar and briefly mix to combine.
- In a separate bowl lightly beat the buttermilk, oil, eggs and vanilla. While the mixer is running on slow, add the wet ingredients to the dry and mix briefly until combined. Then add the cup of hot coffee and lightly mix to combine once more. Take the bowl off the stand mixer and scrape down the sides well and ensure all the batter is well mixed. It will be quite runny.
- Divide the batter evenly between the two pans and bake for 35 – 55 minutes until a knife when inserted into the middle of the cake comes out clean. If necessary, loosely cover the cakes with tin foil from about 20 minutes into the baking to prevent over-browning.
- Cool in the pans for about half an hour and then cool them on a cooling rack.
- Using a stand mixer or electric whisk beat the butter on medium-high speed until pale and fluffy. Add the Icing sugar, coffee and vanilla extract and continue to beat for 3 – 4 more minutes. Add the cocoa powder slowly and when its incorporated add the cooled chocolate mixture. Carry on whipping the icing for a further few minutes and until its extremely light and fluffy.
- To ice the cake place one layer with the dome facing up on a cake plate or stand. Tuck some of the pieces of baking paper used to bake the cake under the bottom of the cake on the plate. This will be removed after the cake is iced and it keeps the edge and plate clean. Scoop a very generous amount of chocolate buttercream icing on the top and spread it to smooth it out. Add the second layer of cake, again with the dome facing upwards and use the remainder of the icing to cover the top.