Preheat oven to 375°F (190°C) and lightly grease a 9x13-inch casserole dish.
Pat chicken dry, season both sides with salt and pepper, and arrange in a single layer in the dish.
Whisk together sour cream, Caesar dressing, and flour until smooth.
Spread the sauce evenly over the chicken.
In a separate bowl, mix crushed croutons, melted butter, and ½ cup Parmesan cheese.
Sprinkle remaining Parmesan over the chicken, then evenly add the buttery crouton mixture on top.
Bake uncovered for 35–40 minutes, or until chicken reaches 165°F internal temperature.
Let rest for 5–10 minutes, garnish with dried parsley, and serve.