La tesorito (teh-saw-REE-taw, lit. little treasure) is the nickname of Laura León, a female actor and singer very popular in the 1980s among male masses of all ages. Her voluptuous body is used to this day as a reference to women ressembling Aztec goddesses of fertility. Other terms with the same connotation are: de a taxista (like taxi drivers like them) and de “libro vaquero” (out of a “cowboy book”, which is an old comic book with luscious drawings).
Usage note: there is no agreement if regarding someone as being a tesorito is derogatory or flattering. It depends on the taste of the interlocutor, which might be fickle.