This 8-layer choc-hazelnut biscuit cake is a guaranteed crowd-pleaser. The decadent cookie layers are spread with a lush coffee cream filling, before being crowned with a luxurious chocolate ganache and sprinkle of roasted hazelnuts and cacao nibs.
Test Kitchen tips
To cut, use a fine serrated knife or a thin-bladed one. Move the knife in a sawing motion without applying too much downward pressure, otherwise the filling will ooze out. Once cut, you can separate the slice into two servings of four layers.
An off-set or cranked spatula or palette knife will make it easier to spread the ganache and coffee cream.
2.Preheat oven to 180°C/160°C fan. Draw two 18cm circles on four large sheets of baking paper. Turn two of the sheets marked-side down onto two large greased oven trays; you should end up with four circles, two on each tray. Reserve the remaining two sheets of paper for second batch.
3.Combine sugar, flours, baking powder, bicarb soda and nutmeg in a large bowl. Make a well in the centre. Whisk egg, milk and butter in a medium jug. Add to flour mixture; whisk until just combined. Spread 1/2 cup of the cake mixture in each circle on trays; sprinkle each round with a heaped tablespoon of combined hazelnuts and cacao nibs.
4.Bake cake rounds for 10 minutes, swapping trays halfway through, or until firm to touch. Transfer cake rounds, still on baking paper, to wire racks to cool.
5.Repeat process with remaining marked baking paper, remaining cake mixture and more nuts and cacao nibs to make eight cake layers in total. Remove lining paper from cake rounds after cooling.
6.Make coffee cream (see steps below).
7.Place a cake layer on a plate or stand; spread with ½ cup of the coffee cream. Spread 1/3 cup of the ganache over the coffee cream, allowing it to drip a little over the edge. Repeat layering, finishing with a ganache only layer. Refrigerate 1 hour.
8.Just before serving, sprinkle with remaining nuts and cacao nibs.
9.Place chocolate in a medium heatproof bowl. Heat cream in a small saucepan over medium heat until just simmering. Pour hot cream over chocolate; whisk until smooth. Stand at room temperature for 2 hours or until thickened.
10.Combine the water and coffee in a small heatproof jug; cool. Beat cream and sifted icing sugar in a small bowl with an electric mixer until soft peaks form. Add sifted cocoa powder and coffee mixture; beat until firm peaks form. Cover; refrigerate until ready to use.
Cake layers can be made a day ahead; layer between baking paper in an airtight container.