Into your roux, stir the chicken soup, pimentos, cream cheese, 3/4 cup shredded cheese and pepper. Add the spaghetti and toss to coat. If needed, add a little of your reserved pasta water until the sauce has a creamy consistency.

Step 5: Bake the chicken spaghetti casserole

Transfer the mixture to a greased 13×9-inch baking dish. Sprinkle with the remaining 3/4 cup shredded cheese.

Cover the casserole and bake for 20 minutes. Then, uncover and bake until the cheese is bubbly, 10 to 15 minutes.

If you have fresh herbs, sprinkle minced oregano, basil or sage over each portion before serving.