Slice Little potatoes in half and dice onion.Place Little potatoes and diced onion into a steamer basket (that safely fits inside your Instant Pot.)
Season potatoes and onions with salt, pepper, garlic powder and gently toss to season evenly.
In the insert of a 6-quart Instant Pot, stir together beef broth, water cream of mushroom soup, dry onion soup mix and steak sauce.
Season both sides of the pork chops with garlic powder and black pepper. Place pork chops into the gravy mixture (doing your best to make sure they get coated with the gravy.)
Place steamer basket (with potatoes and onions) on top of pork chops.
Put the lid on the Instant Pot and set the pressure release valve to "sealing." Set on high pressure for 10 minutes.
When finished, carefully do a quick pressure release.
Remove steamer basket and set aside. Then remove pork chops and set aside.
Turn the Instant Pot to the saute setting. Stir in sour cream (if using.)
To thicken gravy:
Stir together water and cornstarch in a small bowl and add to gravy. Whisk the mixture and allow to come to a gentle boil until gravy thickens.
Serve gravy over pork chops along with a side of potatoes.