• Preheat oven to 180ºC. Arrange hazelnuts on an oven tray and roast for 10 mins.
• Transfer roasted nuts to a clean tea towel and gently rub off the bitter hazelnut skins.
• Transfer 50g of the hazelnuts to the food processor (keep the rest whole for later) and blitz until they form a fine powder.

Base:

• Line a 20cm x 20cm rectangle tin with baking paper.
• Crush the biscuits in the food processor and combine with the pulverised roasted hazelnuts.
• Melt the 120g of butter in the microwave or in a small saucepan over low heat.
• Add the melted butter to the biscuit and hazelnut mixture and stir until combined
• Press into the tin, making sure it is even. Chill in the fridge to set whilst you make the caramel.

Filling:

• Mix together the condensed milk, butter, sugar and golden syrup in a saucepan over a low heat. Stir for 15 minutes until the mixture becomes a darker golden colour and thick. Do not leave this unattended!
• Let the caramel cool slightly before pouring into the tin over your set biscuit base. Press the roasted hazelnuts into the caramel.
• Return to the fridge to set.

Topping:

• Melt dark chocolate and butter in microwave or in a small saucepan over low heat (watch like a hawk so that the chocolate doesn’t burn!).
• Pour over the hazelnut caramel and allow to set in the fridge for a few hours before cutting into squares.