Bordelaise Sauce has appeared on menu’s still in existence as far back as 1882 in the United States.  It is however, French in origin.  While the sauce is still common, I’ve found that not all ‘bordelaise’ sauces rise to the classic concept.
At its core,  Bordelaise is simply a rich sauce consisting of Red wine (hence the similarity of the name to Bordeaux), beef bone marrow, butter, shallot and some other ingredients.   It obviously goes great with just about any beef dish, but I think its best with strips, sirloins, filet steaks.
The Recipe:
2.5 cups of dry red wine (Merlot/Pinot/Bordeaux Blend)
1-2 shallots (to taste)
1/2 cup diced bone marrow
Butter
1.5 oz Veal Demi Glace dissolved in some hot water (not a lot)
Black pepper
In a sauce pot over medium heat, add 2 tbsp of fresh,  unsalted butter. Add diced shallots and saute until translucent, do not caramelize.  When translucent, add wine.  Allow this to reduce to about 1/2-2/3 of  cup (I prefer to reduce to the half cup).
While reducing, you’ll want to remove your beef marrow from the bones. Save the bones to make soup later!  When your wine is finished reducing, add the demi glace to the sauce and gently simmer for 10 minutes.  Do not cook overly long because the sauce will break easily.  Remember, you’re making an emulsion of reduced wine and the marrow.    Prior to serving, pass the sauce through a sieve to remove shallot and any rough bits.  Add 2-3 tablespoons of butter to this immediately before serving to provide a rich glossy, sheen.1-300x219