History traces the first rompope—an eggnog-like drink—back to a 17th-century convent in Puebla, Mexico. In the book Winter Cocktails, author María del Mar Sacasa explains that "according to legend, Sister Eduviges requested that the nuns be allowed to drink the rompope they were only permitted to make. Legend also has it that there was one secret ingredient in the recipe that Eduviges took with her to the grave." Rompope is typically served chilled, often over ice, but it can also be served warm, which is how del Mar Sacasa prefers it when the cold weather sets in. Either way, del Mar Sacasa says, "it’s rich, velvety, fragrant and certainly full of cheer."