Instructions

1. Preheat oven to 180 C (350 F) standard / 160 C (320 F) fan-forced. Grease and line an 8-inch square pan with baking or parchment paper.
2. In a large mixing bowl, add the butter and sugars and beat until pale and creamy. Add the vanilla and egg and beat again until combined. Sift in the flour, baking powder and cocoa powder and stir until combined. Add the chocolate chips and hazelnuts.
3. Place the chocolate batter into your prepared tin and bake in the oven for 30 minutes or until a skewer inserted in the middle comes out clean. Transfer to a wire rack to cool completely.
4. Next, make the hazelnut crumbs. Crush your hazelnuts using a food processor, a mortar and pestle or by hand until they become fine crumbs. In a large mixing bowl, add your hazelnut crumbs, plain flour, sugar, cornflour and cocoa powder. Whisk together.
5. Melt your butter and add it to the mixture, stirring until it forms wet crumbs. Pour this mixture out onto a baking tray lined with baking paper and spread out into one layer. Bake for 10 minutes, then leave to cool completely.
6. To make the chocolate ganache, roughly chocolate dark chocolate and add to a small bowl. Pour over the cream and the pop in the microwave for 20 second bursts, stirring in between, until chocolate has melted. Put the ganache in the fridge for about 15 minutes to thicken.
7. Pour your ganache all over your chocolate slice, then scatter over your chocolate crumbs. Slice into small squares and enjoy!