Roll the risotto mixture into balls about 2 inches in diameter, nesting a cube of mozzarella in the center of each ball.

Fill a countertop fryer with oil or pour a few inches of oil into a large Dutch oven. Heat the oil to 350° to 360°F. (The oil is ready when a 1-inch cube of white bread cooks to golden brown in 40 seconds.)

Set up a breading station: Line up 3 bowls on the counter. Spread the flour our in one and season with salt and pepper. Beat 2 eggs in the second. Mix the grated cheese, breadcrumbs and citrus zest in the third. Coat the balls first in the flour then in the egg and finally in the cheesy breadcrumbs, pressing to make sure the coating sticks.

Fry the rice balls in batches until deep golden and hot through. Drain on butcher paper and serve warm.