In a large saucepan, saute onions and celery in 3 tablespoon of butter until tender. Combine flour and 1 cup of milk. Gradually add to pan. Bring to a boil: cook and stir for 2 minutes or until thickened. Add parsley , seasonings and chicken. Remove from heat. Chill until completely cooled.
Shape 6chicken mixture into six patties, using about 1/3 cup mixture for each patty. Place crumbs and remaining milk in separate shallow bowls. Roll patties in crumbs, then dip into milk: roll again in crumbs.
In a large skillet, cook patties in remaining butter for 3 minutes on each side or until golden brown. Serve on rolls with lettuce and tomatos if desired.
Uncooked patties may be frozen for up to 3 months.