Set instant pot to Saute mode and add oil. Add in chopped onion, garlic and bell pepper and saute for 5-7 minutes or until vegetables begin to soften. 

When vegetables are soft, add in tomato paste worcestershire (or coconut aminos), mustard or mustard powder, onion powder, salt and pepper. Stir until everything is evenly combined.

Quickly add ground beef, break up, stir with vegetables and cook until ground beef is no longer pink.

Add in beef broth and pickle juice and scrape the bottom with your spatula being sure to get the flavorful cooked bits off the bottom. Stir everything together.

Add pasta and make sure it is completely submerged in the liquid mixture to make sure it cooks fully.

Cook on manual high pressure for 8 minutes. Once it’s finished cooking, do a quick or manual release.

Stir in shredded cheese until fully melted and serve hot.