Like the stellar explosion for which it was named, Ardbeg’s Supernova burst upon the single-malt scene in 2009 and then disappeared right after its second bottling in 2010. It was the epitome of an ultraheavily peated Islay whisky, and its absence left a black hole for Scotch-whisky aficionados searching for one of the most robust single malts ever produced. At long last, it’s back, as the Ardbeg Supernova 2014 ($160).

Supernova’s vanishing out of production in 2010 was the result of its popularity, for to …