Beat the eggs well in a medium bowl and add the cheese, and salt and pepper, to taste. In a large, heavy-bottomed skillet, heat 2 tablespoons olive oil over medium-high heat and add the egg mixture. Cook over medium-high heat until the eggs are set, then turn out of the pan. Cut into 12 equal pieces and set aside.
Season each piece of pork with salt and pepper and place 1 piece of cooked egg in the center of each. Top the egg with 1 chard leaf, 1 slice prosciutto, and 1 slice mozzarella. Roll each piece of pork up tightly and secure with butcher's twine or toothpicks.
In a large, heavy-bottomed skillet or Dutch oven, heat the remaining olive oil over medium heat and add the onion and parsley. Once the onion is softened, add the pork fat and, once it is liquefied, add the pork rolls. Brown well on all sides, then stir in the wine and cook at a simmer for 30 minutes. Serve hot, with the pan juices.