The traditional Spanish menu includes some of the best lentils, meat cutlets, and croquettes in Madrid, as well as more elaborate dishes, such as the juicy tortilla con almejas (Spanish omelet with clams). Both locations belong to the same family and are unpretentious inside but are outstanding in terms of quality. The original Prícipe de Vergara location has a tented patio for the summer; the newer one behind the Congress is often filled with politicians. Other location: Zorrilla 7, Centro, Madrid, Spain, PHONE:91/429-8186.