Buy a can of tomato, not spaghetti, sauce, such as Hunt's, Progresso, or Contadina. Make sure it is tomato SAUCE, as sauce is cooked, where crushed tomatoes, diced tomatoes, or tomato puree are not. Then add, let's say, some sauted chopped onion, and salt and pepper to taste. You might also want to simmer your meatballs and/or sausage in the sauce for 30 minutes to an hour to add a bit of meaty flavor. My father has very bland tastes, so onion, salt and pepper are all my mother adds to her sauce in the way of seasonings.