For many of its Longfellow regulars, Merlins Rest might just be the closest bar with cold beer and a comfortably frill-less vibe. However, the unassuming south Minneapolis tavern has a destination-worthy luxury in one of the best whiskey lists in the Twin Cities.

The British Isles-themed bar hangs its tweed hat on its 230-plus choices of Scotch whisky (the Scots' preferred spelling), making it a magnet for aficionados. But Merlins also bests most full-blown Irish pubs in town with roughly 70 whiskeys from the Emerald Isle. "I like to think that we are also the Irish whiskey capital of Minneapolis — if not Minnesota," said proprietor Lee Tomlin, who kicks off his pub's St. Patrick's Day festivities Thursday with an Irish whiskey tasting (7:30 p.m., $35).

The back bar at Merlins Rest is symbolic of the whiskey world's Scotch/Irish split. Despite similar populations and centuries of whiskey-making tradition, Ireland exported just 6.2 million cases, compared with Scotland, which sent out 93 million cases of its smokier spirit.

However, Irish whiskey has been on a decade-long hot streak and a bust doesn't appear imminent. The category as a whole has grown steadily each year and, according to the Distilled Spirits Council, the U.S. alone lapped up 2.5 million cases of Irish whiskey in 2013 — five times more than in 2003. By 2020, the Irish Spirits Association predicts, the country's whiskey exports will double as its number of distilleries jumps from four to 15.

Kieran Folliard is enjoying the Irish upswing. Last month, the former Twin Cities Irish pub magnate took national the Beam-backed 2 Gingers whiskey company he founded, pushing the Kilbeggan-distilled liquor into all 50 states. "It's a fun little leg of the journey, that's for sure," he said while back in Minnesota for a quick breather from a promotional tour. "It's one of those things I certainly wouldn't have predicted when we started out."

Just three years ago Folliard sold his stake in Cara Irish Pubs, which operates Kieran's Irish Pub, the Liffey, Cooper's Irish Pub and former top-selling Jameson bar the Local, to launch 2 Gingers. While Folliard said Irish is the fastest growing whiskey, he's quick to point out that it had significant room for growth.

Irish whiskey was omnipresent in pre-Prohibition America, but was slow to rebound after that and the Irish War of Independence. By the 1960s and 1970s, Irish whiskey was getting trounced by its Scottish brethren and is still light years from catching up.

Although big brands such as Jameson and even the more toffee-hinted Bushmills have reached ubiquity in townie dives and swanky nightclubs alike, Irish whiskey remains underutilized in cocktail bars. But Jack McGarry's trying to change that. He and Sean Muldoon, the decorated team behind New York hot spot the Dead Rabbit, are on a mission to spread the Irish whiskey gospel. "I think it's a case of shouting it from the rooftops and hoping somebody will listen," said McGarry.

Last month the Dead Rabbit launched an ambitious new graphic-novel-style menu revolved around the life of John Morrissey, the 1800s politician and Dead Rabbit's gang leader. More than 40 of the drinks call for Irish whiskey. "I just don't think there's any other category that offers so much diversity and versatility," McGarry said.

While classic cocktail recipes typically use bourbon or rye, McGarry has a few general mixing rules. In shaken drinks he prefers a soft, approachable blended Irish whiskey, favoring single malt and pot still whiskeys such as Jameson Black Barrel in stirred cocktails. "The pot stills are very aromatic," McGarry said. "They're robust and fruity and they can stand up to other ingredients."

Though Tomlin and McGarry agree Jameson makes a serviceable entry-level Irish whiskey, stopping there would be a mistake. For a Jameson alternative, Tomlin suggests other blends such as Paddy, which is made at the same Midleton distillery, or the sweet but not cloying Danny Boy. Tyrconnell makes a nice, round and reasonably priced single malt — an easy first step away from the blends.

McGarry says bourbon drinkers might enjoy Jameson's Black Barrel, which is aged in heavier charred barrels, or the 12-year-old, sherry-finished Special Reserve. Powers John's Lane is another distinguished woody option.

"When it comes to Irish, we have a reputation — well founded — for having a very smooth whiskey," Folliard boasts.

That Irish smoothness is said to come from a third distillation, as opposed to typically twice-distilled Scotches. Of course, there are deviants like 2 Gingers and the peated Connemara (an Islay lovers' Irish), the argument being that some flavor can be lost with each distillation. And as more distilleries join the fold, the Irish whiskey world could get even wider and more colorful.

"Everybody's getting into Irish whiskey," McGarry said. "Nothing's going to change for a few years. It's just going to keep getting better and better."

Michael Rietmulder writes about beer, spirits and nightlife.