Dark reddish-brown in colour, this thick sauce is sweet and spicy. It is made from soy beans, wheat flour, salt, sugar, vinegar, garlic, chilli and sesame oil. It is used as a dip for marinades and other recipes. Sold in jars and tins, it is available from Chinese grocers, delicatessens and some supermarkets. Once opened, it will keep in a screw-topped jar in the refrigerator for several months.