Felix Contreras -- Natalia Lafourcade is a successful singer-songwriter whose voice and music live on the edge of pop, but maintain a distinct independence. A few years ago, while Lafourcade was traveling Brazil, she felt a great nostalgia for her native Mexico and its folk music. When she finally returned home, she immediately called some friends for the kind of party that is ubiquitous in Latin America: lots of social drinking, lots of food and lots of guitars and singing. Classic folk songs were on the playlist and a good time was had by all. Someone recorded the informal jam...