Press SAUTE mode on Instant Pot. Add butter or oil and once it's hot, add Bay Leaf and minced garlic and saute for 30 seconds.
Next, add onions and saute until they soften.
Add Cauliflower florets, water or vegetable stock, black pepper powder, and salt.
Close the lid on the pot, and turn the pressure valve to the SEALING position. Set the pot to MANUAL/PRESSURE COOK (High Pressure) and set the timer to 5 minutes.
When the instant pot beeps, let the pressure release naturally. Open the lid.
Add heavy cream, cheese, and stir well.
Remove Bay leaf and puree the soup using a hand blender until smooth. If you don't have a hand blender, puree in a blender in batches once slightly cooled. Adjust seasoning.
If you think the soup is too thick, you can add water or milk to the soup and boil it for 2 minutes.
While serving sprinkle green onions, oregano and more cheese if required.