In a small skillet over medium-low heat, combine 1 cup of spaghetti sauce with the meatballs. Toss so the meatballs are fully coated and then cover and simmer for 10 minutes, stirring occasionally. If your meatballs are freshly baked, you can just toss them in sauce. (If using store-bought frozen meatballs, you will want to thaw them first.)
1 1/2 cups spaghetti sauce, 16 Italian meatballs