Chocolate Cheesecake

Preheat the oven to 180°C (fan 160°C , gas mark 4). Grease a 20cm spring form cake tin with extra butter and line the base with baking paper.

For the base, crunch the bourbon biscuits into crumbs and place in a bowl. Pour over the melted butter. Mix together then press evenly into the prepared cake tin. Refrigerate for 30 minutes to an hour, until set.

For the filling, place the cream cheese, mascarpone and sugar in a food processor and blend until smooth. Add the eggs, then the cocoa powder, chocolate extract and lastly the melted chocolate, still beating. Continue beating until thoroughly combined.

Spoon the mixture on to the biscuit base in the tin. Level the surface, then bake in the preheated oven for about 50-60 minutes or until the cheesecake still has a slight wobble in the centre. Turn the oven off and leave the cheesecake inside to cool and set for about an hour with the door closed. Take out of the oven, cool, then chill for at least 3 hours in the fridge.

Turn out of the tin, peel off the lining paper and transfer to a serving plate. Dust with cocoa and serve with creme fraiche.