Luis Miguel López Alanís of Morelia, Mexico, writes: Although I grew up in Mexico, it was in Chicago of all places that I learned to cook Mexican food. During the two years I lived there, I missed my country's food so much that I wrote to my mother in Zitácuaro and asked her to send me recipes so I could cook for myself. Now I work as a tour guide in Michoacán, my home state, where I lead tours on Morelia's colonial history and architecture, and show tourists the Paricutín Volcano and monarch butterfly sanctuaries. And sometimes I do restaurant and market tours. Whenever business slows down, I enjoy cooking for my family. Mexico is known for its aguas frescas, delicious cold waters made simply from fruits or vegetables, water, and sugar. They're the perfect refreshment on a hot day.