Preheat oven to 350°. Cook macaroni according to package directions. , Meanwhile, in a large bowl, combine chicken, soup, cheese, spinach, mayonnaise, basil, garlic powder, thyme and pepper. , Drain macaroni; gently stir into chicken mixture. Transfer to an ungreased 2-1/2-qt. baking dish. Toss bread crumbs and butter; sprinkle over casserole. , Bake, uncovered, until bubbly, 40-45 minutes.