200g| 7oz 70% dark chocolatechopped, or chocolate buttons
200g| 7oz unsalted buttercubed
125ml| 4fl oz | 1/2 cup filter coffeeor water
75ml| 5tbsp buttermilk
200g| 7oz soft light brown sugar
100g| 3.5oz caster sugar
100g| 3.5oz plain flour
100g| 3.5oz self-raising flour
25g| 4 level tablespoons cocoa powder
1/4tspbicarbonate of soda
Nutella whipped cream
250g| 8.8oz Nutella or generic hazelnut spread
600ml| 20 fl oz double creamheavy cream
1tspvanilla extract or paste
Chocolate fudge glaze/icing
200g| 7oz 70% dark chocolatefinely chopped
250ml| 8.4fl oz | 1 cup double cream
60ml| 2fl oz milk
3tbspgolden syrupor honey
75g| 5 tbsp unsalted buttercubed
Preheat the oven to 160C (325F). Grease and line three 20cm (8in) cake tins and dust with flour, shaking any excess.
Place the chocolate and butter in a bowl and set over a pot of barely simmering water. Allow them to gradually melt and stir together until smooth.
Add the coffee and use a hand whisk to mix it in.
Combine the eggs and buttermilk in a measuring jug and briefly whisk together to combine. Add to the chocolate and whisk it in.
Combine all the dry ingredients and then sift them over the chocolate. Use a hand whisk to mix the batter together until completely smooth.
Divide evenly between your prepared cake tins and bake for 20-25 minutes until the cakes are firm on top and a skewer inserted in the centre comes out clean.
Cool in the tins for 15 minutes and then carefully remove from the tins and cool on a wire rack. Be gentle as the cakes can be a little fragile.
Make the filling: put the Nutella and vanilla to the bowl of your stand mixer. Whisk for 3-4 minutes on high speed and then use a spatula to scrape the bottom and sides of the bowl.
Lower the speed and add the cream in a steady stream. Increase the speed to maximum and whip until you have firm peaks – be watchful as the cream will split if you overdo it.
Transfer to a piping bag fitted with a round tip and pipe over the cake layers. Sandwich together and pop in the freezer (or fridge) for 10 minutes.
Use a palette knife to add a crumb coating of the Nutella cream over the entire cake. Return to the freezer (or fridge) while you prepare your glaze.
Make the glaze: put the cream, milk and golden syrup in a medium saucepan and bring to the boil over medium-low heat.
Put the chopped chocolate in a bowl and as soon as the cream comes to the boil pour it over the chocolate and set aside for a couple of minutes.
Use a small balloon whisk and stir very gently in the centre of the bowl using very small motions. Be patient and keep stirring very gently until the chocolate melts and turns into a glossy glaze.
Add the butter and stir together until completely smooth. By now the glaze should be still warm enough to be runny but not so hot that it melts your crumb coating.
Take your cake out of the freezer and then pour the glaze over it until it starts to drip down the sides. You can cover the entire cake or reserve some of the glaze for decoration. Let the glaze cool and set slightly before adding any decorations.
If you have reserved some of the glaze leave it to cool completely (in the fridge) then transfer to your stand mixer and whisk until it forms firm peaks. Put in a piping bag fitted with a large star tip and pipe some rosettes on the cake (be careful if the glaze is still wet).
Serve the cake at room temperature but keep in the fridge until 30 minutes before you are ready to serve.
• It is advisable to pipe the filling rather than spread it since the layers can be a bit fragile. • The cake layers can be prepared a couple of days in advance. Once the cake is filled it is best consumed on the same day as it contains fresh cream. • Replace the Nutella filling with whipped ganache, American buttercream or Italian meringue buttercream especially if you need to prepare the cake in advance for an event.