Chasseur means hunter in French, but I can't imagine anyone but the truly desperate hunting a chicken! Chasseur sauce was originally served with wild game birds, and still is. But these days it is served with a variety of poultry and white meats as well. Of course it can vary a bit, but in general a chasseur sauce will include butter, shallots, mushrooms (we could imagine our hunter coming home with a pocketful of mushrooms along with his bird), wine and often times tomato. It is meant to be a rustic sauce and you won't have to fuss over it to get good results. Just don't forget the Cognac!