Bourguignotte Sauce-Lean

Cut a pound of eels into slices being careful that they are very fresh; put these into a saucepan with two quarts of water, two ounces of minced onions and two ounces of mushroom parings, a bunch of parsley garnished with bay leaf and as much thyme, two minced shallots, pepper and all-spice. Set the saucepan on the fire, let it come to a boil, and continue the boiling for twenty minutes, then strain the liquid and reduce it, adding one pint of lean espagnole sauce (No. 416), and a little lean broth (No. 417); let boil once again, despumate it, pour in a quarter of a bottleful of good white wine; boil and despumate again for half an hour, then add another quarter of a bottle of white wine, making half a bottleful in all; Volnay wine is excellent for this sauce. After it is reduced to a proper consistency, and just when ready to serve, incorporate into it a quarter of a pound of crawfish butter (No. 573).