We've recreated this gentlemen's cocktail by using classic bittering agents like gentian root and cinchona bark along with burnt sugar, spices, and a bit of orange peel. Aged in Willett bourbon barrels to allow the flavors to come together and ramp up the intensity.
It is super concentrated so a little bit goes a long way. Best with aged spirits. Stir 1 part No.1 + 4 parts rye in a glass with ice. Garnish with an orange peel.