Preheat oven to 400°F and lightly grease a baking sheet with cooking spray. Slice each chicken breast in half lengthwise to create four pieces, then pound each to a uniform 1/2-inch thickness and set aside.
Combine Italian breadcrumbs, Panko, Parmesan, garlic powder, and pepper in a wide, shallow bowl. Whisk egg whites in a separate bowl until lightly foamy, and divide the mozzarella into four equal portions.
Organize a workstation with the chicken, egg whites, breadcrumb mixture, and baking sheet in order. Dip each chicken piece into the egg whites, shake off excess, and coat thoroughly with breadcrumbs, patting gently to ensure even coverage.
Place chicken on the baking sheet and lightly spray the tops with cooking oil. Bake for approximately 15 minutes until the crumbs are brown and the internal temperature reaches 160°F.
Remove from the oven, top each piece with 2 tablespoons of sauce and a portion of mozzarella, then return to the oven for 3 to 5 minutes until the cheese is melted.
Garnish with basil and serve immediately, adding extra sauce as desired.
