Spray the Instant Pot insert with non-stick cooking spray. Select the Sauté setting and add the halved bacon pieces. Sauté until cooked through and slightly crisp.Remove the bacon and reserve 1 tablespoon of the bacon fat in the Instant Pot.
Add the celery and onions and sauté for 3 minutes.
Add the garlic and cook for another 1-2 minutes until softened. Turn off the Sauté function.Scrape any browned bits sticking to the bottom of the Instant Pot. Use some of the broth if needed (this avoids a burn warning).
Next add the corn and potatoes to the pot, followed by the jalapeños, salsa, green chilies, and seasonings.
Pour the broth into the pot and lock the lid. Seal the steam valve and select manual HIGH PRESSURE for 10 minutes.
In a small bowl, whisk the cornstarch into the milk. Set aside.
Roughly chop or crumble the bacon to prepare for garnishing.
Once the Instant Pot has finished cooking, allow the steam to NATURAL RELEASE for 10 minutes. After 10 minutes perform a QUICK RELEASE to release any remaining steam. Remove the lid once the pressure pin has dropped.
Cut the cream cheese into chunks and drop into the hot soup. Stir well to blend. Add the cornstarch milk mixture into the pot and mix well.
Serve soup warm, topped with shredded cheese, bacon crumbles and sliced green onion.
Be sure to scrape any browned bits of food sticking to the bottom of the Instant Pot insert between the saute and the pressure cooker cycle. This will avoid a burn warning on more sensitive machines.