Set your instant pot to saute, 10 minutes. Heat olive oil in the pan.
When the pot is hot add in the ground beef, garlic powder, paprika, onion powder, salt and pepper. Allow the meat to start browning (about 3 minutes) then add in the celery, onion, carrot, cauliflower rice and potatoes. Saute another 5 minutes until onions and celery appear translucent.
Make sure to scrap all browned bits from the bottom of the pot to avoid a burn notice!
Stir in tomatoes, Worcestershire sauce and beef broth. Cover instant pot and set to seedling, high pressure for 10 minutes.
It will take the instant pot about 10 minutes to come to pressure. Tip: Heat your broth in the microwave before adding to the pot to speed up the time it takes to come to pressure.
When finished cooking, quick release the pressure from the pot.
Check potatoes to be sure they are fork tender, taste for salt and pepper (add more to your liking)
In a separate small bowl, stir together milk and tapioca flour. Stream it into the soup while stirring. The soup should start to thicken almost immediately. If it doesn't you may need to turn the instant pot back to saute to bring the heat back up. Stir in the parsley, but reserve some for garnish.
Add 1 cup of shredded cheddar cheese. I recommend freshly grated here because the pre-grated has stabilizers in it that can cause texture issues. If the soup is too thick for you feel free to add more beef broth.
Top with your favorite burger toppings (pickles, tomatoes, onions, etc) and enjoy!