For readers who want to shake this one up themselves, I've already done the homework: here's the full list of ingredients, bottle by bottle. Now, the story behind the glass.
The Boulevardier was born in Harry's New York Bar in Paris in the 1920s, created for the American expatriate writer and socialite Erskine Gwynne, nephew of the Vanderbilt family. Gwynne founded a monthly magazine for the Parisian American elite called "The Boulevardier", and bartender Harry MacElhone named the drink after him.
Essentially a Negroni with bourbon replacing gin, the Boulevardier languished in obscurity for almost a century, overshadowed by its Italian cousin. The craft cocktail revival of the 2000s pulled it back from the archives, and today it's a bartender's favorite for anyone who loves the bittersweet logic of the Negroni but wants the warmer, toasted embrace of American whiskey.
If the story has tempted you to try this cocktail at home, don't underestimate the role of equipment. A complete barman kit like this one on Amazon gives you all the basic professional tools in one go. And for a more ambitious setup, a professional cocktail bar station is the piece of furniture that takes home bartending to the next level.