To Instant Pot, add potatoes, cold water and 1/2 teaspoon salt. Liquid will not and should not cover the potatoes.
Close the lid, move pressure valve to Sealing and press Pressure Cook on High or Manual for 10 minutes.
After, release pressure immediately by turning pressure release valve to Venting. No need to drain the potatoes but you can, if you wish.
Add butter, milk, garlic powder, remaining 1/4 teaspoons salt and pepper. Mash with a potato masher until creamy and fluffy.
Garnish with fresh herbs and serve hot as a side dish.
Video
Notes
Store: Refrigerate leftovers in an airtight container for up to 3 days.
Freeze: Unlike potato cubes, mashed potatoes freeze well because they are mashed with dairy. Freeze in portions with future use in mind in an airtight container for up to 3 months. Thaw on a counter for 4-5 hours or in the fridge overnight. Warm up on the stove on low with a splash of milk.
Watch sodium: If using salted butter, add less salt.