Cut the bell peppers open around the top by the stem. Remove the seeds and membrane. NOTE: a spoon can be used to scrape out the membrane if needed.
In a medium bowl combine the ground beef, onion, garlic, egg, rice, paprika powder, Italian Seasonings, Worcestershire sauce, salt and pepper. Stir together to fully combine.
Using a spoon divide the ground beef mixture evenly between the prepared bell peppers, set aside.
Combine the tomato paste and the beef broth into the Instant Pot and whisk/stir until combined.
Place the trivet into the Instant Pot and place the bell peppers onto it.
Close the lid, turn the vent to SEALED and select HIGH PRESSURE. Cook for 8 minutes and allow a NATURAL RELEASE for another 5 minutes. Then release remaining pressure and remove the bell peppers from the inner pot.NOTE: The internal temperature of the peppers should reach 165 degrees for the ground beef to be fully cooked.
Mix the cornstarch with ¼ cup of water, set the Instant Pot to SAUTE. Add the cornstarch mixture immediately to the Instant Pot and stir to combine.
Cook until sauce has thickened, stirring often, for about 1 to 2 minutes. Turn the Instant Pot to WARM.
Spoon some sauce over the cooked peppers. If serving on a bed of mashed potatoes or more rice, additional sauce may be drizzled on that too.