Press the Sauté button on the Instant Pot. Wait until the screen says hot, then add the ground beef and sauté until almost cooked through.
Add the onion and garlic and continue to sauté a couple minutes more until the onion is softened and the beef is fully cooked.
Next, deglaze the insert. Add about ¼ cup of the broth and use a spatula to scrape off any brown bits stuck to the bottom.
Add the rest of the broth, then layer on the bell peppers, kidney beans, diced tomatoes, tomato paste, Italian seasoning and salt.
Add the rice on top and push it down until it's just submerged in the broth. Do not stir.
Close the lid, set the vent to sealing and cook on Manual High pressure for 5 minutes.
At the end of cooking time, let the pressure release naturally for 5 minutes, then quick release remaining pressure.
Mix in the apple cider vinegar and season with more salt to taste, if needed.
Serve topped with chopped parsley or finely grated parmesan, if desired.
