Add cream cheese, sugar and flour to your stand mixer bowl or to a large bowl, if using a hand mixer. Work it until smooth and incorporated. Add eggs, one at a time, mixing at all times. Add sour cream, vanilla and lemon zest. Mix until smooth.
Transfer the batter to the cheesecake pan and spread evenly. Wrap a piece of foil around the bottom of the pan. Cut another long piece of foil and fold the long way to create sort of a “rope” to lower and lift the cheese cake into the instant pot.
Pour 2 cups of water into the pressure cooker and set a rack on the bottom. Carefully lower the cheesecake inside the pressure cooker. Lock the lid, select high pressure and set timer for 35 mins.
When done allow a 15 mins natural release then quickly release remaining pressure. Carefully lift the cheesecake from the pressure cooker and place it on a cooling rack.
There will be some moisture on top of the cheesecake, using a paper towel gently absorb the excess moisture. When the cheesecake is completely cooled, transfer to the refrigerator to set for at least 4 hours.