-grated (about 8 oz) Preheat the oven to 350 degrees F. Grease a large baking dish. In a bowl, toss the spaghetti with the butter, and set it aside. Warm the bacon drippings in a skillet over medium heat. Cook the onion, celery, bell pepper, mushrooms, garlic, Worcestershire sauce, and chili powder together until the vegetables are well softened, about 15 minutes; cover the skillet if the mixture appears to be getting dry. Sprinkle in the flour, stirring to incorporate it, and add the beer or stock, the tomatoes, and the chili sauce. Bring the mixture to a boil, reduce the heat to a simmer, and cook the sauce for 30 minutes, until it has thickened slightly and reduced a bit. Remove the pan from the heat, and stir in the half and half and parsley. Pour the sauce over the spaghetti and toss well. Layer half the spaghetti and sauce mixture in the baking dish. Top with half each of the chicken, olives, and cheese. Add the other half of the spaghetti, and top with the remaining chicken, olives, and cheese. (The casserole can be assembled ahead to this point, covered, and refrigerated, overnight. Remove it from the refrigerator 30 minutes before baking it.) Bake the casserole 25 minutes or until the cheese melts and the sauce bubbles heartily around the edges. Serve the casserole hot. Serves 6.