01 - Preheat oven to 400°F. Lightly grease a 9x13-inch baking dish.
02 - Pat chicken breasts dry and season both sides with salt and pepper. Arrange in a single layer in the prepared baking dish.
03 - In a medium bowl, mix Caesar dressing, sour cream, 1/3 cup Parmesan cheese, and garlic powder until well combined.
04 - Spread sauce evenly over the chicken breasts.
05 - Sprinkle mozzarella cheese and 1/4 cup Parmesan cheese evenly over the top. Add Italian herbs if desired for extra flavor.
06 - Bake for 25-30 minutes, or until chicken is cooked through (internal temperature of 165°F) and top is golden and bubbly.
07 - Let rest for 5 minutes before serving. Garnish with fresh parsley if desired.