Pour 1 cup of water in the pot, followed by steam rack.
Load cauliflower florets into a steamer basket and lower on to steam rack, then secure the lid, making sure the vent is closed.
Using the display panel select the MANUAL or PRESSURE COOK function*. Use the +/- keys and program the Instant Pot for 3 minutes.
Meanwhile, add Mash Mixture ingredients to a food processor or blender.
When cooking time is up, quick-release the pressure.
Carefully drain the cooking liquid and transfer cauliflower to the food processor or blender. Process to desired consistency and adjust seasonings as needed.
Transfer the cauliflower to a 7’ x 11” baking dish or shallow casserole.
Top with cheeses and cooked bacon pieces. Set under a broiler 5-7 minutes or until cheese is lightly browned.
Remove from oven and allow to cool slightly until set. Sprinkle green onions over the top and serve.
Notes
*The MANUAL and PRESSURE COOK buttons are interchangeable.