Nigella's Choc Based Lime Cheesecake

What's a girl going to do with all these limes? Gone are the days when you barter your service for eggs, veges or other farm produce. I still have a few lovely elderly patients who will bring in veges or fruits from the backyard or baked goods from the kitchen. I'd rather these than bottles of wine that I don't drink or boxes of chocolates that go onto expand my husband's waistline.

Ingredients:
200g chocolate biscuits
75g unsalted butter

750g cream cheese (I substituted this with 500g cream cheese and 250ml sour cream to make it lighter)
200g caster sugar
4 eggs
Juice of 4 limes
Lime zests

Method:

1. Preheat oven to 180C.
2. Crush the biscuits and melted butter in a food processor.
3. Press onto a springform pan (20cm diameter) and refrigerate while working on the cream cheese batter.
4. Beat cream cheese, sour cream, eggs, sugar and lime juice and zests until smooth.
5. Pour onto the biscuit base and bake in 180C oven for 50 mins.
6. Serve when cooled.