This Guittard chocolate cake is a rich chocolate cake that is so impressive, a real showstopper! Despite the long recipe, it’s not hard to make. Just make sure you follow all the instructions properly, and take the time to cool the sponges before assembling. The results are a moist and irresistible chocolate cake that is so worth the effort! This recipe uses fabulous Guittard chocolate to give a real luxury flavour, but you could use other brands of chocolate, if you prefer. This recipe is from Guittard Chocolate Cookbook (Chronicle Books).
- For the sponge:
- 55g cocoa powder
- 220g plain flour
- 350g caster sugar
- 1tsp salt
- 1tbsp baking powder
- 210ml buttermilk
- 150ml vegetable oil
- 2 large eggs
- 1tsp vanilla extract
- For the ganache:
- 400g dark chocolate chips
- 300ml double cream
- 2tbsp golden syrup
- 85g unsalted butter, at room temperature
- For the buttercream:
- 115g white chocolate (broken into small pieces)
- 130g caster sugar
- 3 egg whites
- pinch of salt
- 1/2tsp vanilla extract
- 340g unsalted butter, cut into cubes, at room temperature
- You will need:
- 2 x 20cm springform cake tins, well buttered
Heat the oven to 180C. In a pan, bring 210ml water to a boil, turn off the heat and add the cocoa powder. Whisk until smooth, then set aside. In a large bowl, combine the flour, sugar, salt and baking powder. With a hand mixer, beat in the buttermilk, oil, eggs and vanilla. Add the cocoa mixture and blend until smooth. Divide the batter between the cake tins and let rest for 30mins at room temperature. Bake for 30-35 mins. Transfer the cakes to a wire rack to cool.
Line a baking tray with parchment paper and sprinkle lightly with sugar. Using a knife, loosen the sides of the cakes and flip onto a wire rack. Leave to cool for about 1 hr. Put the cakes on the sugared baking tray and chill for 1 hr until the cakes are completely cold.
To make the ganache, put the chocolate chips in a heatproof bowl. Set aside. In a pan, bring the cream and syrup just to the boil and pour over the chocolate. Leave to stand for 3 mins, then whisk until the chocolate has melted. Add the butter and stir until combined. Pour the ganache into a shallow baking dish and let cool at room temperature until it is spreadable (at this point, you can wrap the ganache tightly in clingfilm and store at room temperature for up to 1 day.)
To make the buttercream, melt the white chocolate in a bowl over a pan of simmering water. Set aside. Put the sugar, egg whites and salt in a second heatproof bowl and set it over the simmering water. Whisk the sugar mixture continuously until the sugar dissolves and the mixture is thin and warm. Remove from the heat and transfer the mixture to a large bowl. Whisk the sugar mixture on high speed until stiff peaks form, about 5 mins, then turn the speed to low and mix until cool, about 10 mins. add the vanilla and butter on low speed. add the melted white chocolate, in 2 additions, continuing to blend on low, until combined. Increase the speed to medium and beat until the buttercream is smooth and shiny.
To assemble, using a serrated knife, cut both cakes in half horizontally. Put one layer on a cake stand. Spread one third of the ganache on the cake. Repeat until you have 4 layers of cake. Chill the cake for 30 mins. Apply a “crumb coat” (or first layer) of buttercream by spreading half of the buttercream on the top and sides of the cake. You should be able to see some chocolate crumbs in the white frosting. Chill the cake for 15mins to firm up the buttercream. Use the remaining half of the buttercream to apply the final coat. This time you won’t see any chocolate crumbs. It should be completely white.