Simmering chicken stock for a little over one hour reduces it by about two-thirds and thickens it to a glaze. Chicken glaze, or glace de volaille, is a time saver. When you need chicken sauce or soup but don't have the time to make a base, reach for the chicken glaze. If your sauce needs an extra boost of unctuous chicken flavor, enrich it with a tablespoon of glaze. You need quality from-scratch stock to make glaze. Commercial stocks you buy in cartons at the supermarket evaporate and concentrate in flavor during reduction, but they don't thicken.
Strain any aromatic vegetables out of the stock, and pour it into a wide saucepan. Bring the stock to a boil; then lower the heat until it simmers.
Collect the froth from the surface of the stock and discard it. Simmer the stock until it reduces to one-third, or a little over an hour.
Strain the stock through a sieve lined with cheesecloth into a smaller pot. A smaller surface area toward the end of a reduction helps you gauge the consistency.
Bring the liquid to a low simmer, or until you see a few bubbles forming on the surface a few times per second. Skim the surface of the stock as needed.
Reduce the stock until it coats the back of a spoon. If you're storing it, let the reduced stock cool to room temperature and transfer it to an airtight container. Stock stays fresh for two to three days in the refrigerator.
Season soups and sauces made with chicken glaze a few minutes before they finish cooking.
Add water -- 2 times the volume of the glaze -- to the chicken glaze, and bring the mixture to a simmer to return it to its original volume.