01 - Preheat oven to 400°F. Lightly grease a baking dish large enough to fit the chicken breasts in a single layer.
02 - Pat chicken breasts dry with paper towels and place them evenly in the prepared baking dish.
03 - In a mixing bowl, whisk together Caesar dressing, sour cream, 1/2 cup Parmesan cheese, garlic powder, and black pepper until smooth.
04 - Spread the prepared sauce evenly over the chicken breasts to fully coat each piece.
05 - Sprinkle shredded mozzarella and 2 tablespoons Parmesan cheese evenly over the sauced chicken.
06 - Bake for 25 to 30 minutes or until chicken is cooked through (internal temperature reaches 165°F) and the top is golden and bubbling.
07 - Allow chicken to rest for 5 minutes before garnishing with chopped fresh parsley and serving.