To prepare the cake with hazelnut wafer cream, start with the chocolate sponge base (you can also check the recipe Cocoa sponge cake): in the bowl of a stand mixer, pour the whole eggs and the 8 yolks ...

To prepare the hazelnut and chocolate filled cake, start by pouring the whole eggs and sugar into the bowl of the stand mixer (you can use electric beaters and a large bowl as an alternative) (1). Add ...