Smash nub of ginger with the back of your knife. Add ginger to a small sauce pot with the cranberry juice. Heat over high heat until the mixture boils. Reduce to a simmer (low heat) and simmer gently for 20 minutes. Remove the pan from heat, allow the juice to cool, and pour reduced cranberry juice through a strainer to strain out the ginger.

Fill two whiskey glasses with ice. Pour half of the reduced cranberry juice into each glass. Pour 1.5oz of bourbon into each glass. Fill each glass to the top with ginger beer.

Gently stir each cocktail with a spoon and garnish with candied ginger, if desired, and serve!