Preheat the Instant Pot on HIGH saute. Add the bacon pieces and cook until crispy, about 5-8 minutes.

Remove the bacon with a slotted spoon and set aside, leaving about 1/4 cup of bacon grease in the pot.

Add diced potatoes, chicken broth, onion flakes, garlic, salt, and pepper to the pot. Scrape the bottom to remove browned pieces.

Lock the lid and turn the sealing knob to SEALING. Pressure cook on Manual High pressure for 3 minutes.

After cooking, turn the sealing knob to venting for a quick pressure release. If liquid spurts out, close the knob and release pressure in short bursts.

Open the lid and smash the potatoes with a potato masher. Add milk, cream, sour cream, and cheese. Stir completely.

Serve topped with reserved crispy bacon, extra cheese, sour cream, and chives or green onions.