Combining multiple spirits—say, two whiskeys or a split base of rums—is a great way to achieve additional flavor in a cocktail. Combining multiple spirit categories in the same drink, however, takes an especially deft hand. Bartending pro Jillian Vose of The Dead Rabbit in New York City is up to the task, merging two Irish whiskeys with two brandies for the Commander in Chief cocktail. Vose knows a thing or two about Irish whiskey, so that's where she begins. Green Spot is composed of single pot still whiskeys aged between seven and 10 years, and it's full of aromatic spices, barley, toasted oak and green apple. Redbreast 12-year-old, which is triple-distilled and then matured in bourbon and sherry casks, lends spicy, fruity and toasty notes. The whiskeys are joined by Lemorton Pommeau de Normandie brandy (apple and pear with a touch of spice) and a small measure of Giffard apricot brandy (rich fruit with almond accents), which bring extra body and flavor to the cocktail. Mix these spirits with verjus blanc—the tart, fresh juice of unripe wine grapes—plus passion fruit syrup and bitters to round everything out, and you get a unique, complex cocktail that's loaded with fruit, spice and oak. The Commander in Chief is more complicated than your average whiskey drink, but you don't need to concoct any esoteric syrups or intricate infusions; each ingredient is available at liquor stores or online, which means that only a little shopping is standing between you and a drink from a bar that has twice been named the best in the world. 20 Irish Whiskey Cocktails to Try Right Now