What makes them special is:
To stay true to Italian cuisine, use fresh mozzarella or bocconcini (small, bite sized fresh mozzarella balls).
Fresh mozzarella tends to be stretchy and stringy when melted. And soooooo good! If you use fresh mozzarella you want to serve the dish as hot as possible, before the cheese starts to harden. You may want to keep a pair of kitchen scissors handy, just in case.
If you are looking for something less stringy, try low moisture shredded mozzarella or, my favorite, marble cheddar cheese.
Cheddar is more acidic, which makes it less stretchy and more brittle so to speak. This also makes it much easier to serve. No scissors needed. To make sure this dish is perfect, use your favorite tomato sauce. Mediocre sauce will ruin the dish.
Serve with pasta or on a bun. These make superb meatball sandwiches. The best part, you don’t need to do much to create a perfect meatball sandwich – just scoop up a couple of meatballs together with the sauce and the cheese, plop on a bun and enjoy.
