Turn your Instant Pot to saute and add the oil, onions, garlic, and peppers. Cook for 3-4 minutes and add the potato, corn, and seasoning blend. Cook for another minute.
Add the broth, cover and set to pressure cook. Cook for 10 minutes.
Release the pressure and open.
If you want, you can puree some of the soup at this point — remove about half and add it to a blender, blend just a bit and add back to the pot.
Stir in the cheese and milk, and set the pot to warm for a few minutes until cheese is melted and soup is hot.
Ladle into bowls, top with desired toppings, and serve alongside some crusty bread.