From Death & Co
Garnish: 1 orange twist
Stir all the ingredients (except the champagne) over ice, then strain into a coupe.
Top with champagne.
Garnish with the orange twist.
Created by Alex Day, 2009. Inspired by the Chicago Cocktail from the iconic New York speakeasy Milk & Honey, which is essentially a rum Manhattan. The champagne acts more like a garnish, lightening the drink a bit.