1. Cook spaghetti according to package directions, omitting salt and fat. Drain.
2. While spaghetti cooks, heat a large skillet over medium-high heat. Add oil to pan; swirl to coat. Add onion and garlic to pan; cook 2 minutes, stirring frequently. Add beef; cook 4 minutes or until browned, stirring to crumble. Add chili powder and next 5 ingredients (through cinnamon); sauté 30 seconds. Add stock and tomatoes; bring to a boil. Cover, reduce heat, and simmer 10 minutes. Stir in beans; cook 1 minute or until thoroughly heated. Stir in vinegar. Arrange about 2/3 cup spaghetti on each of 4 plates; top each serving with 1 cup chili and 2 tablespoons cheese.