Demi-glace

Reduced stock having the consistency of a light syrup, demi-glace today is simply a reduction of a brown stock by about fifteen times. In classic French cooking (circa 1900), demi-glace was prepared by reducing espagnole, a full-bodied stock thickened with flour. Because the liquid was already partially thickened, less reduction was required and money was saved. The result, however, wasn’t as tasty as well-made modern versions. Demi-glace can also be prepared by repeated moistenings of more meat or fish rather than reduction.