Set your Instant Pot to sauté and add the butter and olive oil. Add the ground beef and sausage and cook about 4-5 minutes or until the beef is no longer pink. Stir with a wooden spoon to break up the chunks of beef so that it cooks evenly.
Allow the meat to cool slightly. Place the cooked ground beef and sausage in a large resealable freezer bag.
Add the onions, garlic, tomato sauce, pizza sauce, Italian seasoning, pepperoni, and beef broth to the bag. In a medium sized bag, add the pasta. Place the shredded cheese in another medium bag.
Take any extra air out of all three bags and close. Staple the bags together above the seal.
Take the meal out of the freezer. Thaw. Place the contents of the large bag into the Instant Pot. Add the pasta. Stir to make sure the pasta is covered with liquid.
Put the lid on the Instant Pot and set it to high pressure for 8 minutes. Release the pressure and wait for the steam to completely stop before opening the lid. Stir in the shredded cheese. Allow it to sit for 1 minute.