A very rich and flavorful brown sauce made from reduction of sauce Espagnole with the addition of wine and veal stock. This is a very long procedure and requires constant skimming. Demiglace is a thick, intensely flavored, glossy brown sauce that is served with meat, poultry, or fish or used as a base for other sauces. It is made by thickening a rich veal stock, enriching it with diced vegetables, tomato paste and Madiera or sherry, then reducing it until concentrated.