In a large bowl add the rice, parsley, Parmigiano and egg (start with one egg) and combine to form a compact mixture.
Into the palm of your hand measure out approximately (you can wear gloves if you prefer) approximately 1 heaping tablespoon of the rice mixture (you can make them smaller if you wish), in the middle place a cube of mozzarella, mold the rice mixture into a round ball, making sure that the mozzarella is completely covered (you will probably need a bit more rice mixture to close it completely). Place the balls on a clean plate until all are formed.
On a clean plate place the bread crumbs and roll each ball in the crumbs. Place the rice balls on a parchment paper lined baking sheet, and chill while the oven is pre-heating, approximately 15-20 minutes.
Pre-heat oven to 400F/200C.
Drizzle the rice balls with olive oil and bake for approximately 25 minutes or until golden brown. Serve immediately.
Notes
A reader mentioned - The easiest way to roll the balls is to chill the rice mixture first and then roll. I find that the mixture stays together better and it is not as sticky.I made 5 each weighed approximately 85 grams / 3 ounces.
Make Ahead and Freezing Italian Rice Balls
Make ahead: Form the rice balls up to a day ahead of time and place in the fridge covered until ready to bake. Bring to room temperature, bake and enjoy. Freeze Italian rice balls: Assemble rice balls (or risotto balls) then flash freeze in a single layer on a parchment lined baking sheet until frozen. Place in a freezer safe bag and store frozen for 3 months. Thaw frozen arancini before baking. Reheating: If you have leftovers, store in the refrigerator then reheat in the oven, air fryer or in the microwave.