For The Best Irish Coffee Drinking Experience, Don't Forget One Prep Step

Irish coffee is a warm blend of delicious flavors with a whiskey kick that can be a cheery holiday drink to sip with an indulgent cheese pairing, a relaxing after-dinner nightcap, a brunch eye-opener on a cold day, or an anytime celebration of its own. Although the comforting beverage is often ordered at a restaurant or bar, making it at home isn't hard, with just four ingredients needed — coffee, sugar, whiskey, and cream. However, there are a few important steps to creating the best Irish coffee, and a key one is preheating the glass.

Unlike the everyday java that you drink from a mug the size of the average coffee pot, Irish coffee is served in an elegant clear glass. They're traditionally tall with a small handle and a short, wide stem, and are often thinner at the bottom, widening towards the top. Part of the appeal of using a glass is that it displays the two layers of black coffee and white gently whipped cream. So what's the secret step?

Preheating the glass helps keep the coffee warm longer by preventing the colder glass from cooling it down, and it also helps the ingredients meld. Fill the glass with hot water, let it sit for about a minute, and then pour it out. Make sure to use heat-resistant glass, so it doesn't crack from the high temperature of the water. If your glass isn't heat-resistant, you can put a teaspoon inside it before filling it with the hot water to help keep it from cracking.

Since an Irish coffee has so few ingredients, you want them to be good quality and balanced. Strong, freshly brewed coffee that's a medium to dark roast will match well with the whiskey. Brown sugar is traditional, bringing more depth of flavor than granulated sugar with caramel notes from its molasses. This is Irish coffee, so Irish whiskey like Bushmills or Jameson (one of the best whiskeys for fall and winter cocktails) is the go-to. Finally, heavy cream that's been lightly whipped will finish the coffee — you want it pourable rather than scoopable.

Once your glass is preheated, you can start assembling the drink. Pour the coffee into the glass and then stir in the brown sugar until it's dissolved. Add the whiskey and mix gently, and then pour the whipped cream over a spoon, so it floats on the coffee. You want to sip the sweetened, boozy coffee through the whipped cream, so leave it on top and don't mix it in. 

You can try out different ingredients and variations for the ones that are traditional. Brew lighter roast or weaker coffee if you don't like it strong and dark. Swap in another flavorful sweetener like honey or maple syrup for brown sugar for a totally different flavor profile. Experiment with a lesser-known Irish whiskey like Ide & Stills, one mixologist's top whiskey choice for Irish coffee, or be a little unorthodox and use a non-Irish whiskey — or even another alcohol like scotch or bourbon. You could whip the cream a little firmer for a fluffier coffee topping, or sprinkle a little cinnamon, nutmeg, or shaved chocolate on top.