Cut the potatoes into evenly sized pieces of about 3/4 inches. At this size, they should be perfectly cooked after a 4 minute cook time in the Instant Pot. If you’re using a different type of potato or you cut the pieces bigger, it may take a bit longer to cook them. If they’re still hard after the 4 minute cook time, you can simply set the Instant Pot to Saute and continue cooking them, uncovered, for a few more minutes, until softened.