The entrecôte should be cut 2 fingers thick. Marinate it in a tablespoon of oil, salt and pepper. Prepare a fire of glowing charcoal and put the meat on the grill. Chop together 4 shallots, a good, firm piece of beef marrow and a little handful of parsley. Turn your steak. On the upper surface spread the mixture, and from time to time press it with the heated blade of the knive, so that the marrow softens. When the entrecôte is cooked, put it on the serving dish, take care not to upset the shallot and marrow mixture which is on top.
This is the old way of cooking the entrecôte à la bordelaise. In times gone by gourmets did not disdain an invitation to go down into the wine cellars and eat an entrecôte with the cellar master and the tonnelier, who had a reputation of preparing it well. They made their fire with hoops of chestnut[!] wood from old barrels, and claimed that this gave a particulary good flavour to the meat.
Paris restaurateurs serve their entrecôte à la bordelaise with a red wine sauce; it does not at all resemble the traditional entrecôte of Bordeaux.
Alcide Bontou, Traité de Cuisine Bourgoise Bordelaise