Press the Sauté button on the Instant Pot and wait for it to heat up. Once hot, add 2 tsp. avocado oil to evenly coat the bottom.
As soon as the oil is hot, add the ground beef and onion, sautéing for 9-10 minutes until beef is no longer pink.
Toss in the diced tomatoes, potatoes, carrots, garlic powder, dried oregano, salt and pepper.
Add the beef broth and stir everything well , making sure the liquid is well-distributed in the pot.
Lock the lid and press the “Manual” or “Pressure Cook” button and set it to cook for 10 minutes under high pressure.
When the soup is finished cooking, manually release the pressure (“Quick Release”). Once the pressure is released, add ½ a bag of frozen corn into the soup (no need to thaw as the heat from the soup will warm it right up).
Serve with your favorite cornbread. I think this soup tastes best the next day, but feel free to eat it right away and then enjoy the leftovers!