Combine the crushed Oreo cookies with melted butter and mix until combined. Transfer to an 8-inch springform pan.
In a high speed blender or food processor, blend the separate Oreos until a fine texture remains.
In a mixing bowl, beat your double cream until stiff peaks form. Add your cream cheese and caster sugar and beat until combined. Using a rubber spatula, fold through the crushed Oreos until combined.
Transfer the Oreo cheesecake mixture onto the chocolate crust. Cover with more crushed cookies and refrigerate for at least 6 hours, or overnight.
Notes
TO STORE: Cheesecake should always be stored in the refrigerator, in a sealed container or covered with plastic. The cheesecake will keep well for up to 2 weeks. TO FREEZE: Freeze leftover portions of the cheesecake, by placing them in a freezer friendly container, and storing for up to 6 months.