You need 2 to 2 1/2 kilos of cooked Italian meatballs, these can be party size (gold ball size) or larger dinner size. You have several options to do this. 1. You can use what ever meatball recipe you are familiar with. 2. Use the meatball recipe on this site, which can be made on the day you are making this recipe, or from frozen as it is a general make ahead type recipe, link is in Recipe Notes section. 3. Last resort, you can use store bought frozen meatballs. If using frozen meatballs, thaw them, if using fresh made AND cooked meatballs, they need to be cooled to room temperature.