Soursop or Other Tropical Fruit Drink

This recipe—so simple I’m almost embarrassed to use the word “recipe”—is meant as a general model for the many aguas frescas based on Oaxaca’s wealth of tropical fruits. When I first started visiting the area, I could never have duplicated these heavenly thirst-quenchers at home in New York. Now I can come close. Today some, though not all, of the fruits for the renowned Oaxacan aguas frescas can be bought in the form of frozen pulp imported from several Latin American countri