Raspberry ripple cheesecake

Put the raspberries, lemon juice and 2 tsp sugar in a small pan and set over a mediumheat. Cook for 7-10 minutes until the berries have softened. Transfer to a foodprocessor and whizz until smooth. Sieve into a bowl, discarding the seeds; set aside.

Whizz the biscuits in a food processor to fine crumbs, add the melted butter andpulse again. Line the base of a 20cm springform cake tin with baking parchmentand grease the sides, then wrap the outside with 2 layers of foil, so that it covers thebottom and sides. Put the biscuit mixture into the base of the tin and press down withthe back of a spoon so it covers the base evenly; chill until needed.

Preheat the oven to 160ºC, gas mark 3. Tip the soft cheese, mascarpone and theremaining 125g sugar into a bowl and use an electric hand mixer to mix until verysmooth. One at a time, beat in the eggs, then carefully fold in the vanilla extract andlemon zest. Pour the cheese mixture over the chilled biscuit base, then dollop overthe raspberry purée and use a skewer to swirl it into the cheesecake. Boil a kettle.

Transfer the cheesecake to a large, deep roasting tin. Pour the just-boiled water intothe tin around the cheesecake, to about halfway up; don’t overfill. Carefully put the tinin the oven and bake for 1 hour 15 minutes-1 hour 30 minutes, until set with a slightwobble. Leave in the roasting tin for 10 minutes, then carefully remove and transfer toa cooling rack to cool to room temperature. Once cool, chill for about 2 hours, untilcompletely cooled. Remove from the tin and slice.