Preheat oven to 400°. Lightly grease an 11" x 8" baking dish with cooking spray. In a large bowl, whisk soup, cottage cheese, sour cream, chives, garlic powder, and cayenne until smooth. Fold in chicken and peas; season with black pepper. Transfer to prepared baking dish and smooth in an even layer. Top with cheddar.
In a medium bowl, combine cracker crumbs and butter. Sprinkle over cheese.
Bake casserole until browned and bubbling, 25 to 30 minutes.
Let stand 5 minutes. Top with parsley (if using).
