Similar to a Negroni (one of our favourite cocktails), the Boulevardier shares two of its ingredients - the Campari and Sweet Vermouth. However in the Boulevardier cocktail Bourbon (or sometimes Rye Whiskey) is substituted for the gin.
The creator of the cocktail was an American-born write - Erskine Gwynne. He created a monthly magazine in Paris called Boulevardier., which existed from 1927 to 1932
Whilst the quantities of each ingredient vary depending on who creates it, the ingredients below are those which are the IBA (Internation Bartenders Association) list.
45ml Bourbon or Rye Whiskey
30ml Sweet Red Vermouth
A twist of fresh orange peel
Pour all of the above ingredients into a mixing glass filled with ice. Stir well to chill the drink, and then strain into a chilled glass. Garnish with a twist of orange peel.