This cheesecake is quite sweet and rich and so should be served in small portions. Expect the cheesecake to crack on cooling.
Cake tin needed: a 20cm (8in) loose-based cake tin or springform tin
for the base
100g (4oz) plain chocolate digestive biscuits
50g (2oz) butter
for the cheesecake
150g (5oz) plain chocolate (39 per cent cocoa solids)
675g (1½lb) full-fat soft cheese
225g (8oz) caster sugar
½ tsp vanilla extract
2 large eggs
Step one Preheat the oven to 160°C/Fan 140°C/gas 3. Lightly grease the tin.
Step two Put the biscuits into a plastic bag and crush finely with a rolling pin. Melt the butter in a medium-sized pan. Remove the pan from the heat and stir in the biscuit crumbs. Press into the prepared tin and leave to set.
Step three To make the cheesecake filling, break the chocolate into pieces and melt gently in a bowl set over a pan of hot water, stirring occasionally. Cool slightly. Measure the cheese into a large bowl and beat until soft. Add the sugar and beat again until well mixed. Beat in the vanilla extract and then the eggs, one at a time.
Step four Spoon half the cheese mixture onto the biscuit crust in dollops, separating the spoonfuls. Add the melted chocolate to the remaining cheese mixture and stir well to mix. Spoon this chocolate mixture in between the plain mixture. Swirl the top with a knife to give a marbled effect.
Step five Bake for about 30 minutes or until the cheesecake becomes puffy around the edges but is still very soft in the centre. Turn off the oven but leave the cheesecake in the oven to cool. Chill well and then loosen the cheesecake from the sides of the tin using a small palette knife. Serve well chilled.