If you want a pint of beer, a shot of vodka or a glass of wine, there are hundreds of bars you could go to. But if you’re looking for a decent glass of single-malt scotch—something more refined than Jack Daniel’s—you need to search a little harder. That’s why a couple of scotch-loving friends and I enlisted the help of local whisky expert Heather Greene, who worked for the Scotch Malt Whisky Society in Edinburgh and currently serves as brand ambassador for Glenfiddich and Balvenie, to take us on a tasting spree at some of her favorite scotch bars in the city.

We started out at the Blue Owl (196 2nd Ave; 212-505-2583), an underground lounge known for its non-pretentious attitude, cozy atmosphere and impeccable cocktails. We were after something else, though—a bottle of 21-year-old Glenfiddich. “Don’t stick your nose in it,” Heather cautioned as we picked up our glasses. Apparently, proper wine-tasting etiquette—putting your nose into the glass and taking a big whiff to capture all the aromas—doesn’t apply to whiskey, as the fumes from the alcohol will burn your olfactory nerves. Instead, Heather encouraged us to sniff our glasses from a couple of inches away. True connoisseurs place a hand over the top of the glass and then gently swirl the whiskey before taking a sharp whiff, she added.

As we examined our scotch, Heather explained that we would be doing a “regressive tour”—essentially, starting with the top-of-the-line, smoothest scotch and then sampling the younger, more harsh whiskeys, instead of the other way around, which is usually how tastings are done. We tried our Glenfiddich 21 neat at first; it was extremely smooth and well-balanced, rich in the mouth and even a bit sweet. Then we added just a touch of water, which is how many whiskey drinkers claim is the proper way to drink it—no scotch on the rocks allowed.

Heather disagrees with this philosophy. “When I was in Scotland, I used to think that the only way to drink single malt scotch was neat or with a tiny bit of water, and anything to change that was sacrilege,” she said in an interview later. “I’ve been back [in the US] and I’m starting to appreciate the American heritage of making cocktails and playing with alcohol to create interesting cocktails. Today is 110 degrees in New York, so for me, when I have a cocktail it’ll be the Glenfiddich 12 on ice.”

After finishing our drinks and polishing off the last of a generous plate of cheese, olives and charcuterie, we were off to hidden hotspot PDT (113 St. Marks Pl; 212-614-0386). We ducked through the phone booth in Crif Dogs to access the dimly lit, snug room that was pleasantly full of couples and small groups sipping on expertly-crafted cocktails and chowing down deep-fried hot dogs. Wedged into a corner by the door, we decided to take care of some essential business first—hot dogs and tater tots for all (well, Heather had a bacon cheeseburger). Our round of Balvenie 12 year arrived, and we savored the flavors of caramel, maple syrup and butterscotch. Though it couldn’t beat the smoothness and complexity of the Glenfiddich 21, it was a solid choice. Heather explained that although most scotches are non-vintage, each distillery has its own recipes that it adheres to year after year. The master distiller is responsible for ensuring that each batch of scotch aged for the same number of years tastes just like the next batch. And because whiskey doesn’t age once it’s bottled, a 12-year-old Balvenie will always taste the same, whether it was bottled 10 years ago or 10 days ago.