Hazelnut and cinnamon-swirl cheesecake

Method

1. For the base, heat the oven to 180°C/160°C fan/gas 4. Put the hazelnuts on a baking tray and roast in the oven for 6-8 minutes until lightly golden. Cool, then transfer to a food processor with the sugar and whizz to fine crumbs. Add the flour and butter to the processor and pulse until the dough comes together. (If you don’t have a food processor, put the toasted nuts in a freezer bag and bash to fine crumbs with a rolling pin. Transfer the crushed nuts to a bowl with the sugar, flour and butter, then rub together with your fingertips until it begins to clump together.) Tip out and lightly knead to make a dough.
2. Press the dough into the base of the prepared tin and smooth to an even layer. Chill for 20 minutes until firm, then bake for 20-25 minutes until golden and sandy to the touch. Set aside to cool completely.
3. Meanwhile, make the caramel. Set a frying pan over a medium-high heat. When it’s hot, sprinkle in the granulated sugar, a spoonful at a time, shaking the pan as you go. The sugar should dissolve almost as soon as it hits the pan. Once all the sugar has dissolved, heat until it turns an amber colour, then stir in the butter. Remove from the heat and pour in the cream, stirring constantly. Be careful, as the hot mixture may spit. Set back over the heat if needed to turn the mixture into a smooth caramel, then set aside to cool for a few minutes. Stir in the cinnamon and cool to room temperature.
4. For the filling, put the gelatine leaves in a bowl of cold water and set aside for 5 minutes. Heat the cream gently in a pan until just steaming. Squeeze the water from the gelatine leaves and whisk into the warm cream to dissolve. Cool to room temperature, then mix in the icing sugar, cream cheese, Frangelico or hazelnut liqueur, if using, and vanilla bean paste until smooth.
5. Stir 1 tbsp of the caramel into the bowl of cream cheese mixture to add some caramel flavour. For the caramel topping, take 4-5 tbsp of this cream cheese filling and add it to the remaining cooled caramel in the pan. Pour the cheesecake mixture over the cooled biscuit base and shake gently to level. Using a teaspoon, start in the centre and carefully drop small dots of the cooled caramel mixture onto the surface of the cheesecake, spiralling outwards towards the edge. Drag the tip of a skewer or cocktail stick through the caramel dots, joining them up as you go, to create a spiral of little hearts (see tip).
6. Put the cheesecake in the fridge for 3-4 hours to set completely. Bring to room temperature for 30 minutes, then serve in slices with any leftover caramel.