Preheat oven to 425 degrees F and line a large baking sheet with parchment paper.
Place your chicken, two breasts at a time, between plastic wrap and use a meat tenderizer or rolling pin to gently pound your chicken to equal thickness. Repeat with remaining chicken breasts and set aside in a large mixing bowl. (see notes)
Drizzle chicken breasts with approximately 1-2 tablespoons of olive oil and sprinkle liberally with salt and pepper and Italian seasoning. Mix well to coat each chicken breast.
Prepare breading bowls. Gather three shallow, medium-sized mixing bowls. The first filled with panko bread crumbs and finely grated Parmesan cheese, the second with flour, and the third with the eggs (whisked well).
Working in an assembly line, dip the chicken first into the flour mixture, then the egg mixture, and finally, the panko mixture, shaking off any excess between additions.
Transfer each chicken breast to the prepared baking sheet and bake until internal temperature reads 160 degrees F (approximately 15-17 minutes).
Remove from the oven and set aside.
For the Homemade Marinara (optional- you may also use store-bought)
As the chicken is baking, prepare the marinara sauce. Heat a large skillet over medium-high heat and add the oil. Add the onion to the skillet and mix well to combine. Sauté the onion for 4-5 minutes, or until starting to soften. Add the garlic and continue to cook for 60 seconds, stirring continuously.
Add the tomatoes (canned and fresh), a pinch of salt and pepper, and Italian seasoning. Mix well to combine and bring to a low simmer. Cover your pot, reduce heat to low, and cook for 5-10 minutes or until tomatoes are soft.
Transfer marinara sauce to a large high-speed blender and process until smooth. Season with salt and pepper to taste.
Transfer half of the marinara sauce to the bottom of a large cast iron (or other oven-safe) skillet. Nestle the cooked chicken breasts into the skillet and top each breaded chicken breast with a spoonful of sauce and a small handful of shredded mozzarella cheese.
Transfer skillet to your oven and broil until cheese is melted (2-3 minutes).
Remove skillet from the oven and sprinkle with fresh chopped basil, if desired. Serve with sautéed zucchini noodles or your favorite cooked pasta.
If your chicken breasts are especially thick, you may want to slice each chicken breast in half lengthwise to create to thinner slices of chicken.
Nutritional information does not calculate zucchini or pasta noodles.