We came across The Boulevardier recipe in The Essential New York Times Book of Cocktails. We highly recommend the book; it’s a great addition to any cocktailian’s library.
4 ounces rye or bourbon
2 ounces Campari
2 ounces sweet vermonth (half and half mixture of Cinzano Rosso and Carpano Antico Formula)
Stir together all the liquor together in a mixing glass filled with ice.
Strain into a cocktail glass (or a lowball glass over ice). Garnish with lemon twist.