Every Monday to Saturday, a steady line of eager customers forms behind a black pickup truck in Lomas de Chapultepec for the fresh seafood cocktails El Jarocho has been serving for the past 40 years. Everyone is at this puesto, or street stand, for the $5 shrimp cocktail with plump shrimp, tangy sauce, and no shortage of sliced avocado, in addition to the hangover-curing "vuelve a la vida cocktail," a refreshing medley of crab meat, fish, oyster, octopus, and shrimp. For $3 extra, you can supersize your cocktail to make it easier to share.