To save time, make the meatballs in the morning and store the balls, uncooked, until you’re ready to cook them. OR, complete all the steps (including cooking the meatballs), and reheat in a large skillet over medium heat. To FREEZE: Cook the meatballs fully and do not add to marinara sauce. Lay on a flat baking sheet or plate and place in freezer until frozen, 3-5 hours, depending on size. Place frozen meatballs in labeled container. When you want to serve them, heat in oven or in marinara sauce on stove.