01 - Preheat the oven to 400°F. Lightly grease a 9x13-inch baking dish with cooking spray or a small amount of oil.
02 - Pat the chicken breasts dry with paper towels. Season both sides generously with salt and pepper. Arrange the chicken in a single layer in the prepared baking dish.
03 - In a medium bowl, whisk together the Caesar dressing, sour cream, 1/3 cup Parmesan cheese, and garlic powder until smooth and well combined.
04 - Spread the Caesar sauce mixture evenly over the top of each chicken breast, ensuring they are completely covered.
05 - Sprinkle the shredded mozzarella cheese and remaining 1/4 cup Parmesan cheese evenly over the sauced chicken. If desired, add the dried Italian herbs for additional flavor.
06 - Bake for 25-30 minutes, or until the chicken reaches an internal temperature of 165°F and the cheese is golden and bubbly.
07 - Remove from the oven and let the chicken rest for 5 minutes before serving. Garnish with fresh chopped parsley if desired.