1. Heat olive oil in a medium saucepan over medium heat.
2. Add onion, garlic, and bay leaves. Sauté about 3 minutes until softened.
3. Stir in Arborio rice.
4. Add chicken stock and bring to a boil. Reduce to simmer and cook about 20 minutes until liquid is absorbed.
5. Remove bay leaves. Transfer rice to a bowl and cool completely.
6. Stir in Parmesan cheese, whole egg, and egg yolk until combined.

Shape the Rice Balls:
7. Divide mixture into 12 equal portions.
8. Mix mozzarella and prosciutto in a small bowl.
9. With damp hands, flatten a portion of rice, add 1 teaspoon filling, and roll into a ball.
10. Repeat to form 12 balls. Place on greased tray.

Coat:
11. Roll each ball in flour, dip in egg whites, then coat in bread crumbs.
12. Chill 30 minutes.

Fry:
13. Heat 2 inches of oil to 350°F.
14. Fry in batches for about 2 minutes until golden brown.
15. Drain on paper towels and serve hot.