Line the inside of a 7-inch cake pan with a large piece of greased aluminum foil (greased side facing up), pushing it into all the edges of the pan.

Crush the cookies in a food processor until they form fine crumbs. Mix the crumbs with the melted butter and press the crumb mixture into the base of the cake pan. Refrigerate while you prepare the cheesecake batter.

Using the paddle on your stand mixer with low speed, or the regular beaters on a hand mixer on low speed, or a food processor (scraping the sides of the processor bowl several times) blend the cream cheese until it is completely smooth with no lumps. When all the lumps in the cream cheese have disappeared, add the sugar. Blend to incorporate the sugar and then add the eggs one at a time, mixing only enough to distribute the eggs in evenly in the batter.

Remove 1 cup of the cheesecake batter and place in a small bowl. Add the creamy peanut butter and stir until combined. Set this peanut butter batter aside.

Add one cup of the chopped peanut butter cups to the remaining cheesecake batter. Gently fold until evenly distributed. Pour cheesecake batter into prepared pan with cookie crust.

Dollop the peanut butter cheesecake mixture over the top of the batter in the pan. Gently spread the mixture evenly to smooth it over and to cover the top of the cake. Cover the pan tightly with more greased aluminum foil.

Place a rack in the bottom of the pressure cooker and add 2 cups of water. Lower the cake pan into the cooker using a sling made of aluminum foil (fold a piece of aluminum foil into a strip about 2-inches wide by 24-inches long). Fold the ends of the aluminum foil into the cooker and lock the lid in place.

Pressure cook on HIGH for 22 minutes.

Let the pressure drop NATURALLY and let the cheesecake sit in the turned off pressure cooker for one hour. Carefully remove the lid and transfer the cheesecake from the cooker to the counter using the aluminum sling or rack. Let the cheesecake come to room temperature and then remove the foil from the top of the cake pan. Blot any liquid that might have condensed on the surface of the cake, wrap it in plastic wrap and refrigerate for at least 8 hours.

Melt the hot fudge sauce in the microwave for about 30 seconds. Drizzle hot fudge across cheesecake and top with remaining chopped peanut butter cups. Bring the cheesecake to room temperature before serving. Dig in!