Serve these Arancini with Rachael's Tomato Basil Dipping Sauce or Buddy Valastro's Classic Marinara Sauce alongside for dipping.
Heat the chicken or vegetable broth in a small saucepot over medium heat. Once bubbling, turn off heat and keep warm on the stovetop.
Heat a large, deep saucepan over medium-high heat with the EVOO. Add the onions and garlic, and cook until the veggies begin to get tender, about 3-4 minutes. Add the rice and white wine along with a pinch of salt and freshly ground black pepper. Cook 5-10 minutes while stirring the rice, allowing the liquid to cook off. Add 2 ladles (about 2 cups) of the heated broth to the rice and cook, stirring constantly, until almost all of the stock has been absorbed into the rice, 5-10 minutes. Add another ladle (about 1 cup) of the heated broth to the rice and continue stirring while the rice cooks and absorbs most of the liquid, about 5 minutes. Add the last bit of heated stock to the rice and cook, stirring constantly, until almost all of the liquid has been absorbed.
Add the butter and 1 cup (2 generous handfuls) of the grated cheese and season with salt and freshly ground black pepper. Transfer the risotto to a large bowl and allow it to cool (to speed this up, spread it out in a large shallow baking dish or baking sheet).
Using your hands, grab a small amount of the risotto and roll it into a 1 ½-inch ball. Make a small hole in the rice ball's center and insert 1 small cube of mozzarella, then cover the hole up with more rice. Repeat until you've used up all of the risotto.
Place flour, beaten eggs and seasoned breadcrumbs in separate bowls, adding the orange zest and remaining ½ cup of grated cheese to the breadcrumbs. Dip each risotto ball in flour, then in the egg, then in the breadcrumb mixture. Reserve the coated balls on a baking sheet and place them in the refrigerator until you're ready to fry them.
In a large, heavy pan or countertop fryer, heat the vegetable oil to 350 °F (use a candy thermometer to check the temperature). Fry the risotto balls, 4 or 5 at a time, until golden brown, 3-4 minutes. Remove with a slotted spoon and place on a paper towel-lined plate. Serve hot with a tomato sauce alongside for dipping.