Escoffier’s demi-glace involved many day’s work. First a brown stock called an estouffade had to be prepared—a 12-hour process at a minimum—from a variety of meats and vegetables. To the finished stock, brown roux, carrots, onions, thyme, bay leaves, tomato puree, and white wine were added in a multi-step process performed over two days to produce a sauce espagnole. Finally the sauce espagnole was slowly reduced over many hours to produce the final demi-glace or reduced even longer to produce a glace.

The following recipe produces a demi-glace or glace in a matter of four or five hours extended over a two-day period. The total “face” time required by the cook is only about an hour. This recipe is based on the methods I have observed in restaurants in France over the last few years. The quantity of ingredients listed in the recipe will produce about 450 grams of glace or about 800 grams of demi-glace. I usually prepare multiples of the recipe and freeze the resulting glace in 300-gram portions—enough for about 8 servings of most sauces. Note: click each picture to enlarge it.

Glace de voilaille
900 grams
chicken wings, chopped into 3-cm pieces
250 grams
chicken feet, chopped
1 medium
leek, all the white and some of the green portion, chopped
1 medium
carrot, chopped
1 medium
onion, roots trimmed, unpeeled, chopped
2 cloves
garlic, unpeeled, crushed slightly
zest from 1
fresh bay leaf
3 sprigs
fresh, flat-leaf parsley
1 tablespoon
tomato concentrate
black peppercorns
2-1/2 liters
cold water

My preferred combination of meat for this recipe is chicken feet and wings in the approximate proportions listed above. I use chicken wings because they are inexpensive and have a high ratio of meat to bone. The feet are used to impart more gelatin to the final glace than would be produced by using just wings. The gelatin causes the final glace to solidify firmly when chilled. I often substitute other pieces of chicken carcass for the wings because whenever I bone a chicken for some other use, I save the bones in the freezer instead of discarding them. I also substitute bones from other meats—the picture has both quail and rabbit bones, as well as chicken carcass, added to the wings and feet. Also, half a cow’s foot or a pig’s foot can be substituted for the chicken feet as a source of gelatin.

In the picture, green onions have been substituted for the leek, which wasn’t available the day I prepared this recipe for the photographs. The green onions could have even been left out, but I had some in my refrigerator that were getting old. If the carrot is scrubbed very well, I don’t bother to peel it. The onion skins are used, especially from brown onions, because they impart some color to the finished glace. Additionally, a whole, chopped pear tomato has been substituted for the tomato paste.

Brown the meat thoroughly in a very hot oven or in oil in a very hot frying pan. Pour off and discard any fat rendered from the meat. Browning the meat will produce a darker glace with more complex flavors, but I often skip this step to save time. The results still have sufficient flavor.
Place all the ingredients in a large stock pot (or divide the ingredients over multiple pots if more glace is being prepared). Place the pot(s) over high heat and bring to a boil. When the liquid begins to boil, gradually reduce the heat to produce a very low boil. As all the contents come up to heat, the level of the heat under the pot can be set fairly low to maintain the low boil. When the water initially comes to a boil, a gray scum will rise to the top. This should be skimmed from the surface with a small ladle or spoon. As the cooking proceeds, the scum will be replaced by yellow fat. This should also be carefully skimmed from the surface. Once the low boil is established at low heat, I check the pot and skim the surface only about once an hour.
The soup is cooked sufficiently when a light broth is produced and the liquid has reduced by about one-third. Retaining as much broth as possible, strain the broth through a fine chinois into a container suitable for chilling the strained broth. As seen in the picture, even though the fat was skimmed, some will still remain. This will quickly form at the surface of the cooling soup. Chill the broth overnight in a refrigerator.
The next day, use a spoon to carefully scrape the congealed fat from the surface of the chilled broth. The broth should be a loose jelly, not liquid, when it is fully chilled. Transfer the jelly to a large saucepan and bring to a full boil. When the broth has been reduced by about one third, a demi-glace will be the result. Reducing the liquid by two-thirds will produce a glace. A convenient way to determine how far the reduction has come is to measure the depth of the liquid with a small metal ruler at the start and then periodically during the reduction. When the liquid has reduced to a glace, it will be syrupy and easily coat the ruler.
When the liquid has reduced sufficiently, ladle it into storage containers and set aside to cool in the refrigerator. The liquid will expand quite a bit if frozen so leave space in the container if you plan to freeze the results. The chilled liquid should be rather firm if reduced to a demi-glace and very firm if reduced to a glace. The demi-glace or glace will last for a week under refrigeration or for many months if frozen. Thaw frozen glace in a refrigerator before using.      
©2004 Peter Hertzmann, Inc. All rights reserved.