“The treasures of the Hispanic Society of America – works by Goya, Velázquez and El Greco, among other masters – are not a popular tourist draw at the group’s Beaux-Arts museum in Washington Heights. But through Sept. 10, the haughty portrait of the Duchess of Alba by Goya and 200 other works from the century-old Hispanic Society are finally receiving blockbuster recognition from thousands of visitors to the Prado Museum here – along with royal accolades, an international prize and souvenir folding fans.”