Chocolate and Vanilla Neapolitan

Preheat the oven to 180 C / Gas 4.

Prepare the vanilla layer: Stir the butter with a fork until creamy. Add the sugar and vanilla to the butter, continue to stir until smooth. Add the egg yolks, mix, then add the flour. Whisk the egg whites until stiff in another bowl then gently stir into the batter. Pour into a buttered square cake tin dusted with flour.

Bake in the oven for 35 minutes. Remove from the oven and cool before removing the cake from the tin. Then cut the cake horizontally to have two pieces.

Preheat the oven to 210 C / Gas 6-7.

For the chocolate layer: Separate the egg yolks from the whites. Whisk the yolks with the sugar in a bowl until white. Add the melted butter, mix, then add the cocoa powder, flour and cornflour to the bowl. Stir well. Whisk the egg whites until stiff in another bowl and fold into the egg yolk mixture. Pour the batter into a buttered square cake tin coated with flour (the same kind of cake tin as for the vanilla cake). Bake for 12 minutes. Remove from the oven, set aside to cool and remove from the tin.

For the ganache: Grate the chocolate in a bowl. Bring the cream to the boil in a saucepan then pour it over the chocolate. Mix.

Putting the cake together: Line a square pan with cling film. Place a layer of vanilla cake first, and brush it with coffee. Spread the ganache mixture, then top with chocolate cake, and brush with some coffee as well. Spread a layer of Nutella, then cover with second vanilla cake and brush with some coffee again. Refrigerate for 30 minutes so that the ganache hardens.