In a large bowl, combine all of the meatball ingredients (ground beef, onion, garlic, breadcrumbs, egg, chopped parsley, salt and pepper). To mix everything, best to use your hands but you can also use a spatula if you like, and mix everything together until just combined. Do not over mix.
Heat oil in a skillet over medium-high heat, add the onion for the sauce, and saute for 2 minutes or until it’s soft. Add garlic and tomato paste, and cook for 30 seconds.
Then add the tomato sauce, and season with oregano, salt and pepper.
Use a 1 or 2 tablespoon cookie scoop to portion out meatballs, to make them round you can roll them between your hands (wet your hands as needed with a little bit of water so the meatball mixture does not stick to your hands).
And immediately drop the meatballs into the simmering tomato sauce.
Cover with a lid, and simmer over low heat for 15 minutes flipping the meatballs halfway through. The internal temp of the meatballs must reach 160°F/71°C. Remove from heat, and serve over rice, pasta, or mashed potatoes.