Cooking time: Just melting the butter
Crush up the biscuits into fine crumbs. Then melt the butter and mix the two together. Press firmly into a 18cm cake tin (i use one with a loose bottom). Beat together the cheese, sugar and lime juice and zest. Spread this on top of the biscuit base and chill for about 30 mins in the fridge. I then grate the chocolate over the top and sometimes a sprinkle of caster sugar although the actual recipe says 50g.