Combine biscuit crumbs and melted butter. Will look a little crumbly but don't be tempted to add more butter as it will press down and moisture will also be added from topping.

Press in a tin lined with alfoil and then baking paper, this will make it easier to get out of your tin later without the baking paper ripping.

Chill.

Beat cream cheese, sugar and vanilla until smooth.

Add eggs and beat till smooth.

Fold in sour cream.

Fold in curd, keeping some aside.

Pour into tin then swirl rest of curd on the top.

Put a couple of inches of water in sc then a rack or scrunched up foil balls.

Place tin in sc making sure it isn't in water then cook on high with tea towel under lid for 3hrs or until centre doesn't have a watery consistency when knife is placed in.

This has a tarty taste so if you don't like that replace lemon/lime curd with caramel, chopped fruit or whole berries :)