Make a breading assembly line with three separate dishes. Pour the flour into a dish, then season with garlic powder, sea salt, and freshly cracked pepper to taste, and mix until well combined. Beat the eggs together in a bowl; whisk well. In a separate dish, combine the Italian panko crumbs and parmesan; mix well.
Slice the chicken breasts in half lengthwise (place your hand on the breast, then carefully cut horizontally), then cut each portion in half.
Dredge the chicken by dipping each piece completely in flour, then egg, and finally the Panko/Parmesan mixture. Place on a plate and repeat with the remaining chicken pieces.
Refrigerate for 30 minutes. Side Note: Don’t skip this step, as it helps the breading adhere to the chicken.
Preheat the oven to 400 degrees. Line a baking sheet with parchment paper.
Pan-fry the chicken by heating the vegetable oil in a large skillet over medium-high heat. Add the chicken to the HOT skillet and cook for 4-5 minutes, or until golden brown.
Flip the chicken over and cook for 3 minutes, or until golden brown. Cook the chicken in batches, if needed.
Remove the chicken from the skillet and place it on the prepared baking sheet.
Spoon a bit of homemade marinara sauce over each piece of chicken, then add the mozzarella cheese.
Bake in the oven for 5-7 minutes, or until the cheese is melty & gooey.
Remove from the oven and sprinkle with freshly chopped parsley.