Combine leftover mushroom risotto with 1 beaten egg, Parmigiano-Reggiano, and a couple of tablespoons of Italian-style breadcrumbs in a bowl.

Adjust consistency by adding more breadcrumbs if the mixture is too soft, ensuring it can be formed into a ball.

Cut bocconcini into small pieces and gently fold into the risotto mixture.

Scoop a tablespoon of the risotto mixture and use another spoon to help form a ball shape.

Lightly flour your hands to prevent sticking, then mold the risotto mixture into a smooth, even ball approximately 3-4 cm in diameter.

In a bowl, whisk the remaining 2 eggs with a pinch of salt and pepper.

Place flour in a separate shallow bowl.

Dip each risotto ball into the beaten egg mixture, ensuring it is fully coated.

Transfer the egg-coated ball to the bowl of flour and coat thoroughly.

Arrange the arancini on a baking sheet and refrigerate for 30-45 minutes to allow them to firm up.

Pour the remaining Italian-style breadcrumbs into a shallow bowl.

Remove the chilled arancini from the refrigerator.

Dip each arancini again in the egg mixture, followed by a generous coating of breadcrumbs.

Return the breaded arancini to the baking sheet and refrigerate until ready to cook.

In a pot or deep fryer, heat canola oil to a suitable frying temperature.

Carefully lower the arancini into the hot oil in batches, avoiding overcrowding.

Fry until golden brown and heated through, approximately 3-4 minutes per batch.

Remove the arancini from the oil and place them on a plate lined with paper towels to drain excess oil.

Serve the mushroom risotto arancini immediately.