Whiz the biscuits, brown sugar and cocoa in food processor until you get a fine meal. Add butter, whiz again to mix. Press into 7-8" loose bottom tin. Chill in the freezer while you get the filling ready, and the oven preheats.

Preheat oven to 180C.

Place all ingredients in bowl of food processor, and blend well to mix, 1-2 minutes on medium speed.

Pour into crust, and bake for around 40 minutes.

Cool completely in the oven, then chill covered in the fridge, preferably overnight.

Place chocolate and cream in a heat proof bowl. Heat in microwave for 1 minute. Whisk​ with a balloon whisk​ until smooth. Cool about 30 minutes, then whisk​ again​. Chill until a little f​irm. Whisk once again till glossy and smooth, and holds peaks. Spread over​ chilled cheesecake. Top with berry of your choice.