The next one, demi-glace, is the richest-tasting meat-based sauce you can make. It freezes well so make plenty. It's really no more trouble to make a double or even triple batch.
Method: Combine Espagnole and stock and bring to a boil. Lower heat to a simmer and reduce liquid to half volume, a quart, skimming if needed. When reduced, strain through a fine strainer to remove any lumps. Add madeira and either serve or cool.
