To the cooled rice, we add the eggs, mozzarella, parmesan, fresh parsley, and a good amount of black pepper. We stir well to combine. Half of the mixture will be vegetarian, so we make these first.
In a ramekin, we microwave the peas with a tablespoon of the sauce for about 30 seconds (the rest of the sauce we refrigerate until right before serving time). We want them defrosted. We set the ramekin next to the large bowl with the rice, and we get two large plates ready, one with the bread crumbs on it, and one to place the balls.
We take a small amount of the rice mixture in our clean hands, which will make a ball about an inch to an inch and a half in size. We form an indentation in the center and add a little of the peas and tomato sauce (only about 3 peas!). We seal up the ball, roll in the crumbs, and place on the plate. We continue until we have used about half of the rice mixture.
We wash our hands again and then refrigerate the vegetarian rice balls—to set for about 30 minutes.
With kitchen scissors, we add the proscuitto to the rice mixture and stir well. We also start heating 2 inches of the canola oil in our Dutch oven for frying. We place our deep-fat thermometer in the pot and watch as the oil climbs to 375° F.
Meanwhile, we assemble the proscuitto filled rice balls—adding peas to the center of these as well. We refrigerate these rice balls and wash up again.
When the oil is hot enough, we start by frying the vegetarian rice balls. We carefully put them into the oil, not crowding them, and fry until nicely browned. We drain them with our spider strainer onto a paper-towel lined plate and sprinkle with salt. (We could have transferred the cooked rice balls to a low oven for a few minutes but we just serve them right away!)
We allow the oil to climb back to 375° F before frying the rice balls with proscuitto. We reheat the tomato sauce in the microwave and serve with the rice balls.