Set Instant Pot to saute and add butter, ground beef and diced onions. Cook until most of pink in ground beef is cooked (3/4 way or so). (if your bacon isn't already cooked you can dice it and add it in now to cook it all together.)
Dice celery and cooked bacon and add into pot, if you haven't added the bacon already. Turn your Instant Pot off.
Add seasoned salt and garlic powder, stir together. Pour in chicken or beef broth and stir.
Close lid and steam valve and set to pressure high for 3 minutes. Do a quick release when done.
Turn pressure cooker off and then press saute, normal, again and add heavy cream and 1 1/2 c. of your cheese. Stir allowing cheese to melt.
Add some of this hot liquid soup to a bowl with your cornstarch and whisk together, then add back into the Instant Pot and stir so it thickens.
Turn Instant Pot off, stir in remaining 1/2 c of cheese and serve topped with additional shredded cheese and chives/green onions or a dollop of sour cream.