Without stocks there would be no French cuisine. Called fonds de cuisine, which translates literally as "foundations of cooking", they are a crucial element in soups, sauces, braises, and stews. Good stocks are made by simmering raw meat, poultry or fish, and bones, with aromatic vegetables and herbs, peppercorns, water and a little salt. Richly coloured brown stocks, made with beef and veal, are made by first browning the meat and bones in the oven before simmering them with rhe remaining ingredients; brown stocks are used in brown sauces and with red meats and game. Light-coloured white stocks, made with veal, poultry and fish, require no browning, and have a lighter flavour suitable for the delicate flavours of poultry, fish and vegetables.
Stocks must be simmered long enough to extract the maximum flavour from the ingredients. For a veal stock, this means at least 3.5 hours, while a chicken stock requires only 2.5 hours and a fish stock just 20 minutes. The stock must be carefully skimmed after it is brought to the boil to remove any fat and grey scum that rises to the surface, but it must never be boiled during cooking, as this would make it cloudy. Stocks may be refrigerated for several days provided they are brought to the boil every day. Or they may be reduced to a thick, syrupy glaze, called a glace, that will set to a very firm consistency when chilled and may be refrigerated for 1-2 weeks (glaces are used as sauce bases or to intensify the flavour of and give body to sauces). Stocks may also be frozen for up to 3 months; freeze in small quantities so that you need thaw only the amount necessary.