Make the crust: Combine the Oreo crumbs with the melted butter in a medium bowl and mix well. Transfer to a 9-inch springform pan and press over the bottom. Refrigerate while you make the filling, at least 30 minutes.
Make the filling: Combine the cream cheese, sugar and vanilla extract in a stand mixer fitted with the whisk attachment. Beat on high speed until smooth and no lumps remain, 3 to 5 minutes. Run a rubber spatula under the mixture to make sure there are no lumps of cream cheese.
Pour in the cream and whisk, starting at low speed then increasing to high speed, until the mixture becomes very thick.
Gently fold in the 1 1/2 cups crushed cookies.
Spread half of the filling over the crust. Scatter the "secret" layer of crushed cookies on top, then add the remaining filling and smooth the surface with a rubber spatula. Tap the pan against the counter to release any air bubbles in the filling. Refrigerate while you make the ganache.
Make the ganache: Place the cream in a small saucepan and bring just to a simmer over medium-low heat. Pour the hot cream over the chocolate in a medium heatproof bowl and let sit undisturbed to melt the chocolate, about 5 minutes. Whisk until smooth, then let sit at room temperature just until cool but still pourable, about 20 minutes. Pour the ganache over the surface of the cheesecake in the pan and spread it with an offset spatula. Tap the pan against the counter to smooth out the ganache.
Refrigerate for at least 8 hours (preferably 12 hours for best results) and up to 2 days. This recipe has no gelatin so it needs longer to set than a regular cheesecake.
Run a thin spatula around the cheesecake, then open the springform pan and carefully remove the ring. Place the whipped cream in a piping bag fitted with a large star tip. Pipe whipped cream rosettes around the rim of the cheesecake then top each rosette with a mini Oreo. Enjoy!
Remove the creme center from the Oreos before you crush them -- you only need the cookies themselves. Alternatively, you could substitute chocolate wafer cookies or whatever cookies or candy bars you like.