Lightly grease a 23 cm (9 inch) diameter springform tin and line the base with baking paper. Finely crush the biscuits in a food processor, then mix in the butter. Spoon into the tin, press firmly over the base and up the side and refrigerate for 20 minutes, or until firm.

Put 1/4 cup (60 ml/2 fl oz) water in a small heatproof bowl, sprinkle evenly with the gelatine and leave to go spongy. Bring a large pan filled with about 4 cm (1 1/2 inch) water to boil, remove from the heat, carefully lower the gelatine bowl into the water (it should come halfway up the side of the bowl), then stir until dissolved. Allow to cool.

Using electic beaters, beat the cream cheese until creamy, add the juice and sugar and beat until smooth. Gently fold in the whipped cream and half the gelatine.

Process the raspberries and extra sugar in a food processor until smooth. Push the puree through a fine-meshed nylon sieve to remove any pips. Fold the remaining gelatine into the raspberry mixture. Place blobs of cheesecake mixtureinto the tin and fill the gaps with the raspberry. Swirl the two mixtures together, using a skewer or the point of a knife. Refrigerate for 4 hour, or until set. Can be decorated with whipped cream and raspberries