01 - Preheat oven to 400°F. Lightly grease a baking dish large enough to fit chicken breasts in a single layer.
02 - Pat chicken breasts dry with paper towels and arrange them evenly in the prepared baking dish.
03 - In a mixing bowl, whisk Caesar dressing, sour cream, 1/2 cup grated Parmesan cheese, garlic powder, and black pepper until thoroughly combined.
04 - Spread the prepared sauce evenly over each chicken breast, ensuring full coverage.
05 - Sprinkle shredded mozzarella cheese and remaining 2 tablespoons grated Parmesan evenly on top.
06 - Bake in preheated oven for 25 to 30 minutes, or until the chicken reaches an internal temperature of 165°F and topping is golden and bubbling.
07 - Allow the chicken to rest for 5 minutes. Garnish with chopped parsley before serving if desired.