Bordelaise Sauce Made with Red Wine Stock

This classic sauce, once made with white wine, is made in a classic kitchen by adding demi-glace or glace de viande to a red wine reduction and finishing the sauce with cubes of beef marrow. The marrow can be replaced with a swirl of butter. The red wine is best reduced along with the demi-glace or glace de viande so the proteins take out some of the tannin. Best of all is a Bordelaise sauce made starting with red wine stock (simply make a veal stock or other stock using red wine instead of