Add water to a 6-qt Instant Pot®. Place metal trivet into the pot.
Pierce potatoes with a fork; place potatoes on top of the trivet. Select manual setting; adjust pressure to high, and set time for 14 minutes. When finished cooking, naturally release pressure according to manufacturer’s directions, about 20-30 minutes.
When cool enough to handle, cut each potato in half lengthwise; top with butter and season with salt and pepper, to taste.