Place a trivet into the base of the Instant Pot, and add the broth. Remove the leaves from the cauliflower, and place it onto the trivet.

Seal the lid, and select the Steam setting for 15 minutes. When the cooking time has been completed, quick release the pressure, then carefully remove the lid and leave it open for 10 minutes.

Use the trivet handles to remove the cauliflower - it should be super soft but not watery. Place it into a large bowl together with the cream cheese and Parmesan. 

Mash everything together until smooth, and season with salt and pepper to taste. Note - for a super smooth cauli mash, you can use a food processor instead. 

Transfer to a serving bowl, and garnish with a little butter and the fresh thyme leaves.