For the base, combine almond flour, ground flax seed, psyllium husk, sugar and cinnamon.
Add the melted butter to mixture and press onto the bottom of the springform pan to create the crust / cheesecake base.
(optional) Bake crust for 10 minutes at 350F using oven or your Instant Pot Air Fryer lid bake function.
For batter, Stir cream cheese and ricotta cheese together.
Then add in the sugar and mix.
Add in eggs one at a time and mix. Batter should become smooth and creamy.
Add in cornstarch and vanilla extract and mix again.
Pour batter on top of crust into the springform pan.
Open Instant Pot. Add 1 cup of water. Place trivet with cheesecake on top.
Close Instant Pot. Select pressure cook, 40 minutes on low pressure or cake function for 40 minutes.
When done, wait for natural release (about 10-12 minutes). Remove from pan and serve.