Preheat the Instant Pot on HIGH saute. Add the bacon pieces and let cook until crispy, about 5-8 minutes. Remove with a slotted spoon and set aside. There should be about 1/4 cup of bacon grease left in the pot. Remove any excess.
To the bacon grease, add diced potatoes, chicken broth, onion, garlic, salt, and pepper. Using a wooden spoon or flat whisk, scrape the bottom of the pot to remove all the browned pieces off the bottom. Turn off Saute Mode.
Lock the lid and turn the sealing knob to SEALING.
Pressure cook on Manual High pressure for 3 minutes. Once pressure cooking has completed, immediately turn the sealing knob to venting for a quick pressure release. If any liquid starts spurting out, close the knob and continue by releasing the pressure in short bursts.
Open the lid and smash the potatoes about 5-8 times with a potato masher. Add the milk, cream, sour cream, and one cup of cheese. Stir completely.
Enjoy by topping each bowl with the reserved crispy bacon, extra cheese, sour cream, and chives or green onions.