Rinse chicken and place in a large soup pot with water and 1 cup broth. Bring to a boil over medium-high heat, then reduce heat and skim with slotted spoon.
Add onion, garlic, thyme, red pepper, sage and bay leaf. Cover and simmer for 20 minutes, then skim again.
Add okra, tomatoes and corn. Cover and simmer for 20 minutes adding pepper.
Cook rice according to directions on package.
Melt butter in a medium saucepan over low heat. Add flour and cook until golden and bubbly, stirring frequently. Stir in 1 cup broth, bring to a boil and reduce heat. Whisk until smooth. Stir into chicken mixture and heat to serving temperature.
Spoon hot, cooked rice into large soup bowls and ladle gumbo over rice.