put rice in blender or food processor or a coffee grinder. Pulse on and off in 2 second intervals until the rice is broken into smaller pieces (about half of their original size).
put rice into a sauce pot with 1 1/4 c water and the saffron. bring to a simmer over high heat, then reduce the heat to medium, season very lightly with salt. cover and cook until all the liquid is absorbed. about 15 mintues.
heat oven to 375.
scrape the rice into a steel bowl with a rubber spatula. add the basil and the parmigana-reggiano. season with salt and pepper.
place in the freezer for about 4-5 minutes to cool.
cut the mozzarella into 12 equal bit size nuggets. remove the rice mixture from the freezer. form into 12 equal size loose balls. place a piece of cheese in center of each ball and then form in a tight ball, sealing in the cheese completely.
repeat until all balls are completely formed, place in freezer for 2-3 minutes to tighten up.
place flour, egg whites and panko in 3 different shallow bowls. lightly season with panko and flour with salt and pepper.
remove balls from freezer coat them in small batches, first coat the ball with flour (knock off excess) then into the egg whites and finally the panko. place finished ball on a baking sheet with a wire rack.
once all balls are coated , place in the oven and cook until he panko is toasted and crisp. if the cheese starts to pop out of the shell, its time to remove from the oven.
heat your tomato sauce and serve with the baked rice balls.