- 50g/2oz butter
- 100g/3½oz digestive biscuits
- 75g/3oz amaretti biscuits
- 50g/2oz soft brown sugar
- 50g/2oz grounds almonds
- 200g/7oz cream cheese
- 200g/7oz ricotta cheese
- juice and rind of lemon
- 1 vanilla pod
- 200g/7oz caster sugar
- 4 eggs, separated
- 150ml/5fl oz double cream
- pinch of salt
- icing sugar
- Melt the butter in a saucepan.
- Meanwhile, crush the digestive and amaretti biscuits in a plastic bag, using a rolling pin.
- Combine the butter, biscuits, brown sugar and ground almonds.
- Press into the base of a greased, 24cm/9½in spring form loose-bottomed cake tin. Chill for 30 minutes.
- Mix together the cream cheese, ricotta cheese, lemon juice and rind, seeds from the vanilla pod, caster sugar, egg yolks and double cream.
- Add the salt to the egg whites and beat until firm, using an electric hand whisk.
- Gently fold the egg whites into the cheese mixture and pour into the cake tin.
- Bake for 30 minutes at 160C/300F/Gas2.
- Increase the heat to 170C/325F/Gas3. For a further 30 minutes.
- Turn off the oven and open the door.
- Allow the cheesecake to cool in the oven.
- Dredge with icing sugar to serve.