Add the water (or the broth) and salt, spices & herbs to the instant pot. Whisk in the polenta.
Set instant pot to 9 minutes, on high pressure.
Manually release, covering the steam spout with a kitchen towel.
Give a good whisk. Add the olive oil (or butter) and cheese, it will thicken a little as it sits.
Taste, adjust salt to taste.
Keep it on the warm function until ready to serve, stirring occasionally.