Preheat the oven to 180°C. Grease and line the base of a 20cm springform tin.
Melt the butter and stir in the biscuit crumbs, mix well. Place in the cake tin and spread evenly, then flatten with a spoon or spatula.
Bake in the oven for 10 mins, until golden. Remove and leave to cool while you make the filling.
Reduce the oven temperature to 160°C.
In a large bowl, beat together the cream cheese and caster sugar until smooth, then add the sour cream and flour and mix again. Add the eggs and vanilla bean paste, beating well between each addition.
Pour the cream cheese mix on to the biscuit base carefully, and bake for 45 mins. The cheesecake should be just set with a slight wobble. The colour should be mainly cream with gold around the edges.
Once finished, turn off the oven and leave the door ajar then leave the cheesecake to cool in the oven – this is supposed to prevent the top from cracking.
Once the oven is cool take the cheesecake out and leave it to cool completely, then carefully remove it from the tin using the spring form base.