To make the crumb crust, put the butter in a 15 cm (6 inch) diameter shallow loose- bottomed cake dish and cook on full (100% power for 30 seconds or until the butter has melted). Stir in the biscuits and nuts and press evenly into the bottom of the dish. Cook for 1 minute.

Beat the cheeses, sugar, egg, lemon juice and vanilla essence thoroughly together in a blender or food processor or mix by hand. Press through a sieve into a jug or bowl.

Cook the filling on full (100%) power for 30 seconds. Whisk and cook for another 30 seconds. Whisk again, then cook for a further 30 seconds, or until thickened. Whisk and pour the mixture into the crumb-lined dish. Reduce the setting to medium low (35%) and cook for 4 minutes, giving the dish a quarter-turn every minute. Leave to stand for 15 minutes, and then chill.

To make the topping, blend the corn flour and 2 tablespoons of the juice from the raspberries in a 1.2 litre bowl and stir in the remaining juice. Cook on full (100%) power for 3 ½ minutes, stirring once, until the mixture thickens to a dropping consistency.

Stir in the raspberries.

Spread the topping over the chilled cheesecake and refrigerate. To unmould, dip the base of the dish into hot water for a few seconds. Decorate with piped whipped cream and mint sprigs.

Blackcurrants or redcurrants could be used in place of the raspberries for the topping.