Barrel-Aged Cocktails By High West Distillery

It was like watching a fire spread: One barrel sitting on a bar in Portland sparked a countrywide frenzy of cocktail aging.

Now that the first wave of experimentation has broken, a second, more meticulous swell is forming–and this time it's not only happening behind the bar.

Utah's High West Distillery is the first producer to join the barrel fray. Using the house rye as the base, distillers David Perkins and Brendan Coyle batched and aged several barrels of Manhattan cocktails for 100 days; now bottled, the 36th Vote ($47) is a complete cocktail in a glass.

The time in oak mellows the components, fusing their respective flavors to create a Manhattan with a velvet personality, silky enough to function as an aperitif–particularly when splashed with soda water.

And behind the bar, the evolution continues as bartenders fine-tune the technique. At The Beagle in New York, Matt Piacentini is rigging a solera system (like those used to make Madeira) to age white Manhattans (made with Dolin sweet vermouth, Buffalo Trace White Dog and Angostura bitters). He fills each of three barrels, then cycles half of the liquid from the top into the second, and repeats with half the contents of the second into the third. When the first of the stuff finally emerges, it'll be an amalgam of 8- to 16-week-old samples.

Next up for Piancentini's barrel exploratory: aged punch.