Heat large skillet over medium heat, add olive oil to coat pan. gently cook meatballs on low-medium heat until slightly browned on all sides. Do not over-cook.
Remove meatballs from skillet and add to prepared sauce. Allow to simmer in sauce for at least 2 hours to allow meatballs to cook thoroughly. I cook mine for about 5 hours in a simmer sauce, this allows nice tender soft meatballs and allows the juices of the meat to infuse in the sauce and vice-verse.