For the Cheesecake
9 ounces chocolate sandwich cookies, such as Oreo
6 tbsp unsalted butter, melted
32 ounces (4 x 8 ounce bars) cream cheese, at room temperature
1 1/2 cups sugar
1/2 tsp salt
4 large eggs
1 cup sour cream
8 ounces semisweet chocolate, melted
For the Chocolate Ganache
1/4 cup heavy cream
4 ounces semisweet chocolate, chopped
Preheat the oven to 325 degrees. Line the bottom of a 9-inch springform pan with parchment paper. Set aside.
In the bowl of a food processor, pulse chocolate cookies until finely ground. Add melted butter and pulse to moisten. Transfer to prepared springform pan and press the mixture evenly into the bottom of the pan. Place the pan on a rimmed baking sheet and bake for 10 minutes. Remove from oven. Set aside to cool.
Wipe out the bowl of the food processor. Combine cream cheese, sugar and salt. Blend until smooth. With the motor running add the eggs, one at a time, mixing well after each addition. Keeping the motor running add the sour cream and melted chocolate. Blend until smooth, scraping down the sides of the bowl as necessary.
Pour mixture onto prepared crust. Bake for 1 hour, until just set. Turn off the oven and leave the cheesecake in the oven with the door closed for 1 additional hour. This will help prevent cracking.
Remove from the oven and run a thin knife around the edges of the cake. This also will help prevent cracking. Once the cake is cooled, cover loosely with plastic wrap and place in the refrigerator for at least 6 hours, or overnight.
When ready to serve, prepare the ganache. In a small saucepan, bring cream to a boil. Remove from heat and add chocolate. Stir until melted. Set aside until thickened, about 2-5 minutes.
Carefully unmold the cheesecake from the springform pan and pour the chocolate ganache over top.