Creamy Wild Rice Soup

1/2 cup wild rice
5 cups chicken broth
4 tablespoon butter
1 large carrot, sliced
1 medium onion, chopped
\2 stalks celery stalks, chopped
1/4 pound fresh mushrooms, sliced
2 tablespoons flour
1/4 teaspoon salt
1/4 teaspoon white pepper
1 1/2 cups chopped chicken

Combine 2 1/2 cups chicken broth and wild rice in saucepan.  Bring to a boil over medium high heat.  Reduce heat to low; simmer, covered until rice is tender. about 1 hour.  Drain and set aside.  Melt butter in saucepan over medium heat.  Add carrot, cook and stir for 3 minutes.  Add chopped onion, chopped celery and sliced mushrooms cook and stir until vegetables are tender, 3 to 4 minutes.  Remove from heat.  Whisk in flour, salt and white pepper until smooth. 
Gradually stir in remaining 2 1.2 cups chicken broth.  Bring to a boil over medium heat; cook and stir until thickened, about 1 minute.  Stir in chicken.  Reduce heat to low and simmer, uncovered until soup is heated through, about 3 minutes.  Spoon 1/4 cup cooked wild rice into each serving bowl.  ladle soup over rice.