You're gonna need some lime
Juice a lime fresh at the last minute and add 1/2 ounce lime to a cocktail shaker.
Just a little sweetness
Add 1/2 ounce simple syrup to the shaker.
It's ok to be bitter
Add 3/4 ounce Campari to the shaker.
Though earlier versions of the recipe call for golden rum, blackstrap adds tons more flavor. Add 1.5 ounces Cruzan blackstrap rum to the cocktail shaker.
Big ice cube
Lieberman serves this drink over a big ice cube in a copper Moscow Mule mug.
Fill shaker with ice. Seal and shake very well, until cocktail is quite cold.