Quilquiña (Porophyllum ruderale) is the pungent raw herb at the heart of Bolivian and Andean cooking — the same aster-family plant known in Mexico as papalo, but claimed here by a wholly different kitchen. Its blue-green, oil-dotted leaves taste like cilantro amplified into something wilder: a green, citrus-and-rue rush with a soapy, almost gasoline-like edge. Pounded raw into llajwa, the fiery table salsa of Bolivia, it is the signature aromatic of highland and valley cooking around Cochabamba.