Preheat the Oven:
Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish with cooking spray or butter.
Prepare the Sauce:
In a large mixing bowl, combine the cream of chicken soup, sour cream, milk, garlic powder, onion powder, paprika, and a pinch of salt and pepper. Stir until smooth.
Combine Ingredients:
Add the shredded rotisserie chicken, cooked pasta, frozen vegetables, and ¾ cup of shredded cheddar cheese to the bowl with the sauce. Mix until well combined.
Assemble the Casserole:
Pour the mixture into the prepared baking dish and spread it out evenly. Sprinkle the remaining ¼ cup of cheddar cheese over the top.
Prepare the Breadcrumb Topping:
In a small bowl, combine the breadcrumbs and melted butter. Mix until the crumbs are evenly coated. Sprinkle the breadcrumb mixture over the casserole.
Bake:
Bake in the preheated oven for 25–30 minutes, or until the casserole is bubbling and the topping is golden brown.
Serve:
Let the casserole rest for 5 minutes before serving. Garnish with fresh parsley if desired.