In a large soup pot, combine broth, tomato paste, salt and spices. Whisk until blended. Add raisins, onion, garlic, yams, chickpeas and chicken. Bring to a gentle boil. Reduce heat to low, then cover and simmer for 20 minutes. Add green vegetables and cook another 10 minutes or until chicken is no longer pink and yams are soft. Serve stew over rice or millet.