Add graham crackers and sugar to the bowl of food processor and pulse a couple of times, until small crumbs form.
Melt butter in microwave or on stove top and add to graham cracker mixture. Pulse until just combined.
Pour graham cracker mixture into bottom of greased cheesecake pan and press the mixture firmly into the bottom of the pan and nor more than one inch up along the sides.
Place pan with crust into the freezer for 15 minutes.
Filling
Blend together cream cheese, sugar, flour, grated peels, vanilla bean caviar and vanilla extract until smooth.
Add eggs and yolk, one at a time, mixing just to combine.
Fold in cream thoroughly.
Pour filling into the pan, on top of the graham cracker crust.
Cook
Add 1.5 cups of water to the bottom of your pressure cooker and then place a trivet inside the pot.
Cover the cheesecake first with a paper towel and then with a piece of aluminum foil and loosely secure the foil.
Place cheesecake into pressure cooker using a sling.
Lock pressure cooker cover into place. Set the pressure to high for 35-40 minutes. Allow a 10 minute natural release.
After all pressure has been released, open pressure cooker and gently remove the pan. Remove the foil and paper towel and dab off any liquid that may have accumulated.
The center (no more than an inch) will be slightly jiggly (not wet, JIGGLY), but don't worry. The heat that is trapped inside will continue to cook the center while the cheesecake cools.
Topping
Mix together the sour cream and sugar and then spread on the hot cheesecake.
Let cool on wire rack for one hour.
Lightly cover and place in refrigerator overnight.
Notes
If there is liquid on the top of your cheesecake, put it back into the Pressure Cooker for 5 more minutes with a 10 minute Natural Pressure Release.Any kind of Crispy Cookie Crumbs can be used, such as Nilla Wafers, Shortbread, Ginger Snaps, Chocolate Thins, Biscoff, Oreo, Lorna Dune, etc. Biscoff Cookies work best for the crispest crust.Use extra flour if you want a denser filling and/or add 5 minutes to your cook time.Up to a 7.5" pan will fit comfortably in a 6 qt. Pressure Cooker. If you have a 7-7.5" pan and want a taller cheesecake, increase the recipe by one-half and increase cooking time to 40 minutes. Otherwise, if using the recipe as is, in a 7-7.5" pan, reduce cook time to 32 minutes.If using the mini 4 inch pans, divide into three mini pans and cook for 12 minutes, with an 18 minute Natural Pressure Release. If using 5 inch pans, cook for 17 minutes, with an 18 minute Natural Pressure Release.For an 8 inch Cheesecake, double the recipe and cook for 40 minutes, with a full Natural Pressure Release.For Single Serving Jar Cheesecake 8 oz Wide Mouth Glass Jar - cook 7 minutes 4 oz Wide Mouth Glass Jar - cook 4 minutes 16 oz Glass Jars - DON'T DO IT! 15 minute Natural Pressure Release