Preparation

• For the crust:
  Preheat the oven to 325°F. Process the cookies in the bowl of a food processor. Add the butter and pulse until moistened. Press into the bottom and halfway up the sides of a 9-inch springform pan. Bake for 10 minutes. Let cool slightly.
  
  For the filling:
  Melt the chopped chocolate until smooth. Let cool.
  
  In the bowl of an electric mixer, beat the cream cheese until smooth, about 1 minute. Add the sugar, cream, and cocoa powder and beat** until well combined. Scrape down the sides and bottom of the bowl. Add the eggs, one at a time, beating just until smooth. Beat in the melted chocolate until just combined. Do not to overbeat.
  
  Pour the batter into the cooled crust. Place the springform pan on a rimmed baking sheet and bake for about 50 minutes, or until the top looks slightly dry and the middle is slightly wobbly. Turn off the oven and crack the oven door open and allow to cool for 10 minutes as this helps prevent cracking. Remove the cheesecake from the oven to a wire rack to cool to room temperature.
  
  Refrigerate until completely chilled, at least 4 hours. Release the cheesecake from the pan onto a cake stand or serving plate.
  
  
  For the topping:
  Place the chocolate in a medium heatproof bowl. In a small saucepan, heat the cream just until simmering. Pour over the chocolate. Let sit for 3 minutes before stirring until the mixture is melted and smooth. If needed, allow to cool and thicken. Pour over the cheesecake.
  
  ** Do not overbeat the batter as it adds air which causes the cake to crack in the center when cooked as it cools.