Lemon meringue cheesecake

For the meringue: preheat the oven to 110C/gas 1/4. Line 1-2 baking trays with non-stick baking parchment and set aside. Whisk the egg whites in a large, clean bowl until stiff but not dry, then gradually whisk in the sugar and vanilla extract to make a stiff meringue mixture. Pipe the meringue into small peaks on the prepared baking trays and bake in the oven for about 2-3 hours or until crisp and dry. Remove from the oven, leave to cool, then remove from the paper.

Meanwhile, for the biscuit base and cheesecake filling: put the custard creams and melted butter in a blender or food processor and blend together until well mixed. Divide the crumb mixture equally between 6 metal chefs' rings pressing down to level the surface. Set aside.

Put the water, lemon zest and 1 teaspoon of sugar in a small pan and bring to the boil, then reduce the heat and simmer for 2 minutes. Remove from the heat and set aside to cool.

In a bowl, mix together the mascarpone cheese and remaining 25g of sugar, then fold in the whipped cream. Fold half of this mixture into the melted chocolate, then fold the chocolate mixture into the remaining mascarpone mixture, together with the cooled lemon mixture, stirring well. Spoon the lemon mixture into the chefs' rings over the biscuit base, dividing and spreading it evenly. Chill in the fridge for several hours or until set.

For the lemon curd: put the lemon juice and butter in a heavy-based pan and heat gently until the butter is melted. Whisk in the egg yolks, whole eggs and sugar and bring gently to the boil then simmer for 4-5 minutes until thickened, whisking continuously. Remove from the heat and set aside to cool.

To serve, unmould the cheesecakes and place on serving plates. Smear the tops of the cheesecakes with the lemon curd, then arrange the meringues on top. Decorate with the spun sugar, fruit coulis and mint sprigs.