1. Combine pork, onion and garlic in 4- to 5-quart slow cooker.
2. Combine chili powder, cocoa, cinnamon, allspice, cayenne and cloves; add to slow cooker, tossing to coat meat and onions with seasonings.
3. Stir in tomato puree, vinegar, Worcestershire sauce and bay leaf. Cover and cook on High for 4 to 5 hours (Low: 8 to 10 hours).
4. About 30 minutes before serving, carefully poke 4 holes in the spaghetti squash using a sharp knife. Microwave on High (100% power) in 5 minute increments until done, about 10 minutes. Poke the squash with a sharp knife every 5 minutes. When the knife slides in pretty easily, the squash is done. Let stand 15 minutes.
5. Slice squash in half lengthwise with sharp knife; scoop out seeds. Use a dinner fork to scrape out spaghetti strands. Divide spaghetti squash between
6. Remove bay leaf from chili; salt and pepper to taste. Spoon chili over squash. Top as desired with cheese, onions and beans.