Pour water into Instant Pot. Place steamer rack or basket in the pot. Layer potatoes on steaming rack so they are elevated above the water. Lock lid, seal, and cook potatoes on manual high pressure for 8 minutes.
While potatoes cook, mix milk and butter together in a small saucepan on medium heat until warm. Set aside.
Flip the valve to quick release pressure once potatoes are done. Transfer to a bowl and mash. Pour in milk mixture and mix with a spoon until creamy and fluffy. Sprinkle in garlic salt, salt, pepper, and any additional desired herbs. Serve while warm. Enjoy!
Notes
Keeping the skins on allows for greater nutrition value, however you can peel them for a more smooth texture.
Feel free to add extra herbs like parsley, rosemary or thyme
If you love the cheesy factor, add in some cream cheese.
Adjust the milk ratio for varying potato textures if you prefer them more stiff or soft.