Like fashion, the realm of cocktails can be a fickle place. One day you're in, and the next you're out. But, just as happens on the runway, trends come and go — and come again. And each incarnation brings with it subtle nuances and updates on an old classic.

Such is the case with Grappa. The Italian liqueur once known as a poor man's drink is having a moment, easing its way back into the spotlight and giving better-known digestifs like Sambuca and Limoncello a run for their money.