Preheat oven at 160 C (140 C if using a fan forced oven)

Prepare cheesecake base
Use a food processor to blend biscuits and butter until you get a smooth sticky mixture (you can also use your hands to crush biscuits and combine with butter). Press the mixture over the base and side (about 4-5cm or 1 1/2 inch high) of a 22cm springform pan. Refrigerate for 30 minutes.

Make the cheese mixture
Beat the Philadelphia, Mascarpone, sour cream and lemon rind into a bowl using an electric mixer, until smooth. Add the eggs and beat until they are combined with the cheese.

Make the lemon curd
Add the butter, caster sugar, egg, lemon rind and lemon juice in a bowl and stir well. Cook the mixture over a water bath (place the bowl over a pot with gently simmering water) for about 20 minutes, stirring constantly. The lemon curd is ready when it coats the back of a spoon. When the cheese mixture is ready, remove from heat, cover with plastic wrap and set aside.

Cook the cheesecake
Remove the biscuit base from the refrigerator and pour in the cream mixture. Bake in the preheated oven for 1 hour. Cool the cheesecake and pour the lemon curd on top, making sure it gets evenly distributed. Refrigerate for 3-4 hours before serving.

You can serve it topped with fresh berries and dusted with icing sugar.