• Preheat oven to 325°F.

Make the crust:

• In the bowl of a food processor, process the cookies until they are fine crumbs.
• Remove 22 grams (about ¼ cup) of crumbled Oreo and place in a small sealed container. You’ll use this later for topping the cheesecake.
• Add the butter to the food processor and pulse until moistened.
• Press into the bottom and half up the sides of a 9-inch nonstick springform pan.
• Place the pan on a rimmed baking sheet and bake for 10 minutes. Maintain oven temperature.

Make the filling:

• While the crust bakes, in the large bowl of an electric mixer, beat the cream cheese until smooth.
• Add the eggs one at a time, blending after each addition until just combined. Scrape down the sides and bottom of the bowl.
• Add the sugar, sour cream, and vanilla, and beat on low speed until combined. Be careful not to overmix.
• Using a spatula, fold in the Oreo cookies.
• Pour the batter into the baked crust. This will fill your pan to about 80%, but don’t worry about it overflowing in the oven.
• With the pan still on the baking sheet, bake for about 1 hour, or until set. The edges and top should look slightly dry. If the middle is somewhat wobbly, that’s fine. Err on the side of underbaking rather than overbaking.
• Turn off the oven heat and open the oven door by 1 inch. I use a wooden spoon to keep it open. Let the cheesecake cool inside the oven for 30 minutes. This helps to prevent large cracks from forming.
• Run a thin-bladed, flexible knife around the edge of the cheesecake to make sure it's not sticking to the sides of the pan, which can cause cracks as it cools.
• Let the cheesecake cool completely to room temperature on a wire rack, about 2-3 hours. Refrigerate overnight until completely chilled, or for at least 5 hours. Release the cheesecake from the pan onto a serving plate or cake stand.

Make the ganache:

• Place the chocolate chips in a medium heatproof bowl.
• In a small saucepan, heat the cream just until simmering. Pour over the chocolate chips.
• Let sit for 3 minutes before stirring until the mixture is melted and smooth. Let cool slightly until thickened.
• Pour over the cheesecake and smooth evenly. Place the cheesecake in the fridge to slightly set the ganache while you make the whipped cream.

Optional: Make the whipped cream:

• Use an electric mixer to beat the cream, powdered sugar, and vanilla on high speed until stiff peaks form.
• Using a spatula, spread half of the whipped cream evenly over the cooled and slightly set ganache. Smooth to meet ganache at the edges of the cheesecake.
• Place the remaining half of the whipped cream in a piping bag fitted with a Wilton 1M tip. Pipe swirls around the outer edge of the top of the cheesecake.
• Lightly sprinkle the saved Oreo cookie crumbs on top of each piped swirl, then pour the remaining crumbs in the center of the cheesecake, gently spreading evenly.