In a large bowl, mix ground beef, egg, bread crumbs, Parmesan, Italian seasoning and salt. Divide evenly and roll into 12 meatballs.
Add the marinara sauce, diced tomatoes, and water to the Instant Pot. Gently place the meatballs on top.
Turn to manual, high pressure and cook for 8 minutes. Once the time is up, release any pressure.
Serve the meatballs over spaghetti or in sub buns.
Notes
Adding water helps avoid the burn notice, if your sauce is too thick, you may see a burn notice.To thicken the sauce further, remove the meatballs after cooking and simmer the sauce on “SAUTE” for a few minutes. Let cool slightly as the sauce will thicken as it cools.