1. Sautee onions in oil until tender but not browned Combine, mustard, flour,salt, pepper, and brown sugar to onions and stir.
2. Stir in the rest of the ingredients.
3. Bring to a boil while stirring constantly.
4. Turn down heat and simmer for 20 minutes stirring constantly.
5. Marinade par-boiled chicken pieces in sauce for at least one hour (or overnight) or baste pieces as you grill.