Using a large mixing bowl, beat together the cream cheese and sugar and cocoa until combined and creamy
Beat in the sour cream until combined
Beat in the melted chocolate and vanilla until combined
Beat in the eggs, one at a time until combined
Remove crust from freezer and pour the cheesecake batter into the crust
Cover the cheesecake with foil
Place 1 cup of water into the pot of the instant pot
Place cheesecake onto trivet and into the pot
Cover the pot with the lid and turn the knob to sealing
Set to high pressure for 35 minutes
Once the timer goes off, allow for a natural release
Remove the lid and pull cheesecake out
Place onto a wire rack to allow to cool completely
Place into fridge overnight