Chicken Breasts Pierre

6 skinless, boneless chicken breast halves
1/4 cup all-purpose flour
1/2 teaspoon salt
1 pinch ground black pepper
3 tablespoons butter
1 can stewed tomatoes with liquid
1/2 cup chicken stock
2 tablespoons brown sugar
2 tablespoons balsamic vinegar
2 tablespoons Worcestershire sauce
1 teaspoon salt
2 teaspoons chili powder
1 teaspoon mustard powder
1/2 teaspoon celery seed
1 onion, chopped
1/8 teaspoon cayenne pepper

In a shallow dish or bowl, combine flour, salt and pepper.
Coat chicken breasts with flour mixture.
Melt butter in a large skillet over medium heat, and brown chicken on all sides.
Remove from skillet, and drain on paper towels.
In the same skillet, combine the tomatoes, onion, stock, brown sugar, vinegar and Worcestershire sauce.
Season with salt, chili powder, mustard, celery seed and cayenne.
Bring to a boil; reduce heat, and return chicken to skillet.
Cover, and simmer for 35 to 40 minutes, or until chicken is tender, no longer pink and juices run clear.

Note
I used 6 skinless, boneless chicken thighs.