Nothing beats the intense flavor and silky texture of a homemade demi-glace, but making one takes time: a full day or more of roasting bones, simmering stock, and reducing the sauce to its caramelized essence. There are, however, a few acceptable shortcuts. We experimented with several store-bought demi-glaces and found two versions—D'Artagnan's Veal Demi-Glace and Natural Classics DemiGlace—that work well in a pinch for making classic the sauces. They have the requisite meaty, slightly sweet flavor and are made according to the same method many cooks use—essentially a large-scale version of the home-style technique we shared. Those two sauces don't contain preservatives or stabilizers and must be kept chilled or frozen until they're used. Most store-bought versions, however, such as Williams-Sonoma Demi-Glace de Veau or More Than Gourmet Demi-Glace de Veau Gold, are shelf stable but have a less subtle taste and a far thicker texture. Thickened with starches and heavy on salt, these sauces work the best when you use them as you would other concentrates, like tomato paste—that is, as a flavoring and coloring agent. We recommend using a tablespoon or so of these latter two to enrich stocks for braising or to add depth of flavor to rice dishes, particularly risottos.