Put noodles, bone broth, and cream into the Instant Pot.
Set to manual and dial down to 7 minutes. Make sure the vent on top is closed.
Allow to cook. Then open the vent valve on the top of the Instant Pot and allow steam to release. When it stops hissing, you can open the lid.
Stir in cheese, butter, salt, and pepper.
Serve immediately.
If you have some leftovers, store them in the fridge. To rewarm your gluten-free mac and cheese the next day, just heat over low heat in a saucepan and add a little more cream or butter.