1. In a large pot, brown the ground beef over medium heat. Drain excess fat.
2. Add chopped onion and minced garlic to the pot. Cook until the onion is translucent.
3. Stir in chili powder, cinnamon, cumin, allspice, and cloves. Cook for another minute.
4. Add cocoa powder, beef broth, tomato sauce, apple cider vinegar, Worcestershire sauce, brown sugar, salt, and pepper. Stir well.
5. Bring to a boil, then reduce heat and let simmer for 2 hours, stirring occasionally.
6. Serve chili over cooked spaghetti. Top with shredded cheddar cheese, chopped onions, and kidney beans as desired.