Lime Drink

Mexican limes are small, with a thick, very dark green skin and a refreshing flavor that is close to that of a U.S. lime but not quite the same. Only the rind of the fruit is used in this simple Oaxacan favorite, which I learned to make from Lucila Zárate de Fuentes of Oaxaca City. Her version differs from some in that the grated lime is added only at the very last moment before serving. When the drink is allowed to sit for a while before serving it turns a wonderful green-yellow color, but