This particular Arancini or the Suppli al Telefono is prepared with sauteed chopped button mushrooms and finely minced onions. They were formed into the balls and coated with flour. Then packed in vacuum sealed bag and kept frozen until needed. It gave me a wonderful surprise. I am not sure because the freezing and defrosting it caused the mixed Parmesan-Reggiano and Fontina cheeses to become more flavorful or what it is, the fried arancini burst with flavor at the first bite into it. It really is a satisfying snack or eat them as an entree.