In a small saucepan, warm the whiskey over low heat for 1-2 minutes. Be careful not to boil.
Pour the hot coffee into a preheated coffee mug.
Add the warmed whiskey and brown sugar to the mug and stir until the sugar is fully dissolved.
In a separate bowl, whip the heavy cream until stiff peaks form.
Gently pour the whipped cream over the coffee mixture, using the back of a spoon to keep it in place.
For an extra touch, sprinkle some ground nutmeg or cinnamon on top of the whipped cream.
Serve and enjoy your classic Irish coffee!
Notes
For a sweeter drink, add more brown sugar to taste.You can also use Bailey's Irish cream instead of whiskey for a creamier and slightly less strong version.For a non-alcoholic version, simply omit the whiskey and add a dash of vanilla extract for flavor.