When using Rosina frozen meatballs you do not need to thaw them first before cooking
Feel free to add extra herbs and spices to change it up such as red pepper flakes or fresh basil
I like to use mozzarella and parmesan but any good melting cheese you have will do
When using mozzarella make sure to use pre-shredded so there isn't a lot of excess moisture
Leftovers can be eaten cold or reheated but make sure the casserole is piping hot throughout
Since the meatballs were already frozen I don't recommend you re-freeze this dish