Prepare a 7.5 inch springform pan with non-stick cooking spray. Wra aluminum foil around the bottom to protect from water seepage.
In a food processor, place 20 Oreo cookies and pulse until it makes fine crumbs. Slowly add the melted butter and pulse until the cookies come together into a ball.
Remove and save 3 tablespoons of the Oreo crumbs.
Press the remaining cookie crumbs into the springform pan. Place in the freezer for 10 minutes while the batter is prepared.
In a medium bowl, beat cream cheese until soft and creamy. Add the sugar and continue beating until fluffy, about 2 minutes.
Add the Nutella, eggs, heavy cream, flour, and vanilla and beat just until combined.
Transfer half of the mixture to the springform pan and spread evenly. Sprinkle with the reserved Oreo crumbs. Pour the rest of the cheesecake batter over the Oreo crumbs. Cover the springform pan to avoid water dripping onto the cheesecake.
Place the trivet in the bottom of the electric pressure cooker liner. Add the minimum required amount of water according to the manufacturer’s instructions. Lower the cheesecake into the pressure cooker.
Cover the electric pressure cooker and set the valve to sealing. Program for manual or “pressure cook” for 35 minutes.
When the cooking cycle is complete, allow the electric pressure cooker to naturally release the pressure until the pressure pin drops. Remove the lid and allow the cheesecake to continue cooling inside the pressure cooker for 20 minutes before removing.
Replace the aluminum foil with plastic wrap and refrigerate the cheesecake for at least 2 hours prior to serving.
Run a knife around the edge of the springform pan before removing.
Prepare the ganache by placing the heavy cream, Nutella, and butter in a microwave safe bowl. Heat on hgh for 1 minute. Stir until completely blended. Cool slightly, stirring often.
Place the cheesecake over a wire rack. Pour the ganache over the top of the cheesecake.
Make the whipped topping by beating the heavy cream and powdered sugar until stiff peaks form. Transfer the whipped cream to a piping bag and garnish the cheesecake with 8 stars around the edges. (Reserved the remaining whipped topping for serving.)
Cut the remaining Oreo cookies in half and place one half cookie over each star of whipped cream.