Melt the butter and sugar in a pan over gentle heat then take off the heat and stir-in the biscuit curmbs. Press this mixture evenly into the bottom and slightly up the sides of a greased loose-bottomed 20cm cake tin. Place in the refrigerator and chill for 2 hours.
Remove the vanilla seeds: Slice the vanilla pod in half lengthways, leaving the tip intact, so that the two halves are still joined. Holding onto the tip of the pod, scrape out the seeds using the back of a kitchen knife.
Make the filling: Place the soft cheese, sugar and vanilla seeds in a bowl, then beat with an electric mixer until smooth. Tip in the cream and continue beating until the mixture is completely combined. Add the remaining filling ingredients and mix.
Now spoon the cream mixture onto the biscuit base, working from the edges inwards and making sure that there are no air bubbles. Smooth the top of the cheesecake down with the back of a dessert spoon or spatula. Leave to set in the fridge overnight.
Carefully lift from the tin and set on a work top. Pipe the whipped cream as a border around the edge of the top of the cheesecake then fill the centre with the stewed blackcurrants. Chill in the fridge for about 3 hours and serve.
To stew blackcurrants: use 250 gms blackcurrants (tinned, frozen or fresh) add 3 Tbs water and 3 Tbs sugar, bring to the boil and then simmer until the currants burst and then reduce down slightly to get rid of most of the liquid.