Serves 8 Ingredients For the cake: 175g: unsalted butter, really soft, diced, plus more for the tins 175g: self-raising flour, sifted 1tsp: baking powder 3 eggs, lightly beaten 100g: golden caster sugar 75g: light muscovado sugar 1tsp: vanilla extract For the frosting: 500g: mascarpone 1tbsp: black treacle 1tbsp: golden syrup 2tbsp: light muscovado sugar For the Caramel Hazelnut Wisps: 30 hazelnuts, blanched and roasted 24 fine, pointed wooden skewers 110g: caster sugar Preparation 1. Preheat the oven to 180C. 2. Butter two 20-cm round sandwich tins and line the bases with baking parchment. 3. Use an electric mixer with beater attachment, but use a food processor, or a bowl and an electric whisk, if you prefer. Sift flour and baking powder into a bowl, add butter, eggs, two types of sugar and vanilla extract, and beat until well blended. Do not over-mix. 4. Divide the batter between the tins, level the tops and bake for 20-25 minutes until a skewer emerges clean. Remove from the oven, leave in the tins for a couple of minutes, then turn out on to a wire rack. Remove the papers and leave to cool completely. 5. Butterscotch frosting: Tip mascarpone into a bowl and beat in treacle, syrup and sugar. Spread a layer on top of both cakes and sandwich them together. 6. Caramel Hazelnut Wisps: make sure you have both a small and a large bowl of cold water, and a heavy kitchen board to hand. The oven should be turned down to 170C. 7. Roast the hazelnuts for 5 minutes. Cool completely then carefully insert the point of a skewer very gently into each nut. 8. Spread newspaper out on the floor and lay a large sheet of baking parchment on it. Place the heavy board on a surface directly above. 9. Put the sugar and 100ml cold water into a heavy-based saucepan and, over a low heat, allow all the sugar to dissolve, stirring with a metal spoon. Use a damp pastry brush (make sure it’s not nylon) to wipe away any sugar crystals from the side. 9. When you can no longer see any crystals, increase the heat to a high boil. Do not stir. It will turn a beautiful golden amber. Drop a piece into the small bowl of cold water. If it crackles and forms a ball, it’s ready. Plunge the pan into the large bowl of water and leave to thicken up for a few minutes. 10. Take a skewered hazelnut and dip into the caramel. Lift, allowing excess to drip into the pan and, when it forms a thin strand, secure the skewer under the heavy board so the caramel can drip on to the baking parchment on the floor. Repeat with all the hazelnuts - you should end up with 20-24 wisps. 11. If the caramel hardens, return to a very gentle heat to soften. After five minutes, the caramel wisps will have hardened. Snap the lengths as you wish (mine are 10-12cm long). Very carefully remove the skewers and place the wisps - if possible - directly on to the cake. If not possible, then temporarily rest upright in piece of sugarpaste or buttercream to stop them from rolling around and breaking, and keep in a cool, dry place.