Avgolemono
Avgolemono is a family of sauces and soups made with egg yolk and lemon juice mixed with broth, heated until they thicken. Avgolemono can be used to thicken soups and stews. Yuvarlakia is a Greek meatball soup made with rice and meat meatballs that are cooked in liquid. Avgolemono is added to the soup to thicken it. Magiritsa soup is a Greek avgolemono soup of lamb offal served to break the fast of Great Lent. As a soup, avgolemono usually starts with chicken broth, though meat (usually lamb), fish, or vegetable broths are also used. Typically, rice, orzo, pastina, or tapioca are cooked in the broth before the mixture of eggs and lemon is added. Its consistency varies from near-stew to near-broth.[citation needed] It is often served with pieces of the meat and vegetables reserved from the broth.
Source: Wikipedia