In a large pot, bring 6 cups of water to a boil. Add pearl onions and boil
3 minutes. Drain and rinse in cold water, peel and set aside.
In same pan, sauté sliced onion, carrot and celery in 1 tablespoon butter
until tender. Remove from pot and set aside.
Add chicken to pot and brown on both sides. Remove from pot and keep warm.
Add wine and simmer till reduced to 1/2 cup.
Stir in broth and seasonings. Return chicken to pot, cover and simmer for
5 minutes or until juices run clear.
Remove chicken to a platter and keep warm.
Combine flour and milk until smooth and gradually stir into pan. Bring to
a boil, cook and stir for 2 minutes or until thickened.
Return vegetables to pan and remove from heat, cover and set aside.
In a nonstick skillet, sauté reserved pearl onions and mushrooms in remaining
butter until tender. Add the onions and mushrooms to platter. Discard bay leaf
from sauce. Spoon over chicken and vegetables.