Glace de viande is a sauce made by reducing meat broth or stock until rich and condensed.
2 quarts brown beef or veal stock, strained and thoroughly degreased
Pour the stock into a heavy non-reactive pot and bring it to a simmer over medium heat.
Reduce the heat to low and let the stock cook until it has reduced to 2 cups, stirring from time to time.
Transfer the stock to a small, non-reactive pan and heat over the lowest possible heat until it is reduced to ½ cup.
Strain the glaze into a jar.