One of the happiest benefits of our mini-boom of Peruvian restaurants is a new appreciation for pisco, the unaged, pot-stilled grape brandy that is the national drink of Peru. And though there are myriad cocktails in which you can sample this colorless and heady spirit — which tastes vaguely like vodka but with a richer viscosity and the faint aftertaste of the grapey fruit — there is none better than a good pisco sour. The essentials of this historic drink have changed little since the first recipe was published in Lima in 1903 by S.E. Ledesma. A 2-oz. dram of pisco (traditionally a "puro" made from a single grape called quebranta) is blended with sugar, lime juice, and an egg white, then shaken vigorously and poured into a chilled glass, where its foamy head is artfully dotted with Angostura bitters.
What makes one pisco sour better than another? As always, it's a matter of balance and craftsmanship. I've had some that were simply too sour, too sweet, crunchy with stray ice, gaudily garnished with too much bitters, or served sloppily shaken with a loose foam that looked like broken meringue.
But the bartenders at Vista Peru in Old City have it down. Their rendition of the classic is at once bracingly refreshing, rounded at the boozy edges, aromatic with just enough cinnamon spice from the Angostura and crowned with a tight, creamy foam of twice-shaken egg whites that floats across the top of the frosted cocktail like a cool mist hovering in the Andes Mountains. For a subtle upgrade, step up to a higher-end pisco like Barsol, which adds a bit more depth of flavor and smoothness.
— Craig LaBan