Learn how to create mashed potatoes in the Instant Pot.
Place your quartered potatoes in the Instant Pot. Add enough water to come up the potatoes 1/2 to 3/4 of the way.
Seal the Instant Pot and cook at high pressure for 10 minutes. Allow for natural release.
Drain the potatoes. Then place them back in the pot. If using a ricer, run the potatoes through that first. If not using a ricer, mash the potaties with a potato masher or back of a wood spoon.
Add butter and salt to taste. Slowly add in the milk, only using what the potatoes need. Using a hand mixer or a whisk to just combine. Don't overwork them.
Set the Instant Pot to warm until ready to serve.