Lightly grease a 7-inch spring form pan. Fold a long piece of foil into a sling, 5-6 inches wide and about 20 inches long. Place the rack in the bottom of your Instant Pot and pour in 2 cups of water.

To make the crust, combine the chocolate cookie crumbs and melted butter. Press into the bottom of the prepared pan. Place pan in freezer while you make the filling.

With an electric mixer, beat the cream cheese and both sugars until well combined. Add eggs and egg yolks, one at a time. Stir in sour cream.

Add vanilla, salt and flour. Mix until creamy, scraping down the bowl often. Stir in the melted chocolate until smooth.

Pour the mixture over the prepared crust and smooth the top. Cover tightly with foil. Place the pan on the foil sling and carefully lower it into the pressure cooker. Fold the foil sling down so that it doesn't interfere with closing the lid.

Lock the lid in place. Select high pressure and set the timer for 30 minutes. When beep sounds, turn off pressure cooker (unplug it). Use a natural pressure release for 10 minutes, and then a quick pressure release to release any remaining pressure.

Remove the cheesecake from the pressure cooker using the sling and transfer it to a cooling rack for one hour. Transfer the cheesecake to the refrigerator to chill overnight before serving.