Definition: liaison

This is a process used to thicken a liquid such as a sauce, soup or cream. It can be done with flour or starch mixed with cold water and poured into the boiling liquid, or with egg yolk or cream when finishing a sauce or soup, but be careful, egg-based thickeners must never be boiled. Thickeners made from coral, blood or cream are among the many possible options. In modern cooking, cold starches, seaweed and pectins are now used.