Preheat the oven to 350 degrees F. Grease a 9-inch springform pan with butter. Set aside for a minute.
In a blender or food processor, pulse the Oreo cookies until they are fine crumbs. Add the melted butter and pulse again until the mixture resembles damp sand.
Pour the Oreo and butter mixture into the bottom of the springform pan. Lightly press the crust into the bottom of the pan. Bake for 10 minutes. Remove the pan and allow it to cool.
Add the eggs one at a time, mixing well between each addition. Add the vanilla extract.
Pour the cheesecake filling over the Oreo crust, smoothing the top with a spatula. Bake for 45-50 minutes, or until the edges are set and the center isn't too jiggly.
Turn off the oven and open the door partway, allow the cheesecake to cool in the oven for 15 minutes. Remove the cheesecake to a wire rack to allow it to cool completely. Refrigerate for at least 4 hours.
Once the cheesecake has cooled and been refrigerated, add the chopped dark chocolate and heavy cream to a microwave safe dish and microwave in 30 second intervals. Whisk the mixture between bouts in the microwave until it is completely smooth.
Pour the ganache on top of the cheesecake. Add salted peanuts. Slice and eat.