Add trivet rack to the instant pot and add 1 cup water.
Remove husks from your ears of corn (or you can keep them on if you want to trim them down and husk them after the corn is cooked) and place in the instant pot. Lay 2 or 3 corn ears down first, then 2-3 on top of them, facing the opposite direction.
Secure the instant pot lid and set the valve to sealing. Cook on Manual (High pressure) for 3 minutes.
When the timer beeps, quick release any remaining pressure and then remove the lid.
Use tongs to carefully remove the hot ears of corn from the pot. Serve warm with butter, salt and pepper.