Wikipedia
Lechazo
Lechazo is a Spanish dish made from "cordero lechal". The meat used is from unweaned lambs, and is similar to veal, or the meat of "cochinillo", Spanish suckling pigs. The province of Castilla y Leon has a distinctive version of lechazo referred to as "Lechazo de Castilla y Leon". Aranda de Duero is known as the heart of the dish, with numerous restaurants that specialize in lechazo and feature "hornos de leña", or wooden stoves, in which the lamb is roasted.
The lamb used in lechal must derive all its nutrition from its mothers milk, and must be no more than 35 days old and weight between 9 and 12 kilograms at the time of slaughter.