Slice each chicken breast lengthwise to make four thinner chicken cutlets. If needed, lightly pound the thicker areas so the pieces are similar in thickness.

In a large bowl, whisk together the eggs, parsley, minced garlic, salt, and black pepper. Add the chicken and turn each piece until evenly coated. Let the chicken marinate for 20 minutes.

In a shallow dish, combine the breadcrumbs, grated Parmesan, and garlic powder. Lift each piece of chicken from the egg mixture and let the excess drip off. Press the chicken firmly into the breadcrumb mixture until evenly coated on both sides.

Heat the oil in a large skillet over medium heat. Fry the chicken in batches until the coating is crisp and golden on both sides. Transfer the chicken to a plate.

Carefully pour off most of the oil from the skillet and remove any dark or burnt crumbs, leaving a small amount of oil behind. Add the chopped onion and cook over medium heat until softened. Stir in the minced garlic and cook for about 30 seconds, just until fragrant.

Pour in the tomato passata, then add the salt, black pepper, oregano, coriander, and sugar. Stir well and simmer uncovered over low heat for 7 to 8 minutes, until the sauce has slightly thickened.

Preheat the oven to 400°F (200°C). Arrange the fried chicken on a parchment-lined baking sheet or in a baking dish. Spoon 2 to 3 tablespoons of tomato sauce over each cutlet, top with shredded mozzarella, then sprinkle about 1 teaspoon of Parmesan over each piece.

Bake for 10 minutes, until the cheese is melted and the chicken is cooked through. The internal temperature should reach 165°F (74°C). Let the Chicken Parmesan rest for 2 to 3 minutes before serving.