In a large bowl, with a handheld mixer, mix the cream cheese and sugar on medium speed until smooth.
Blend in the peanut butter, heavy cream, vanilla and flour.
One at a time, mix in the eggs and egg yolk.
Pour the batter over the crust and cover the pan with foil.
Make a sling by folding a long piece of foil lengthwise to make it strong. Place the cheesecake on the sling and gently lower onto the trivet.
Lock the lid and cook at high pressure for 50 minutes.
Turn off the pressure cook and do a natural release for 10 minutes and then a quick release.
Remove the lid and foil, and using an instant read thermometer in the center of the cheesecake, make sure the cheesecake has reached 150 degrees farenheit. If it hasn't, place everything back on and cook an additional 5 minutes, 10 minute release and check the temperature again.
Remove to cool and remove the foil.
After it's cooled, place in the fridge for 3-4 hours or overnight.