1. Place the Oreos (with filling) in a food processor. Pulse a few times to crack the cookies into smaller pieces. Process until finely crushed.
2. Melt the butter in a small saucepan or microwave on medium power for about 20-30 seconds.
3. Pour the melted butter into the Oreo crumbs and stir until well combined.
4. Lightly grease a 6-inch round pan with a removable bottom.
5. Firmly press the crumbs into the bottom of the pan. Refrigerate for half an hour.
6. Melt the chocolate in a double-boiler or microwave on medium power, stopping to stir every 30 seconds until smooth. Let it cool at room temperature.
7. In the bowl of an electric mixer fitted with the whisk attachment, place the cream cheese, powdered sugar and vanilla extract. Beat until smooth.
8. Add the heavy whipping cream and beat on medium-high speed until stiff peaks form.
9. Turn the mixer to low speed and pour the melted chocolate into the mixture. Beat until just combined.
10. Spread the filling evenly into the pan over the Oreo crust.
11. Refrigerate for 30-40 minutes.
Ganache layer:
1. Melt the chocolate in a double-boiler or microwave on medium power, stopping to stir every 30 seconds until smooth.
2. Add the fresh cream and stir until smooth.
3. Pour the ganache over the cheesecake and spread evenly with a spatula.
4. Refrigerate for 6 hours or overnight.