For a different and more authentic Sicilian version of the rice ball filling...Make a bechamel sauce (easy), it's a mix of butter, flour and milk. Thicken it with parmesan and mozzarella cheeses.
Yesterday on the show I mentioned making riceballs over the holidays. Here is a video of the basic recipe with my friend Alicia Vitarelli. Later today I will post an alternate recipe for a different filling. Buon appetitto!