Final answer:
Combining whiskey, kirschwasser, cynar, and amaro is grounds for a Boulevardier cocktail according to Mr. Boston.
Step-by-step explanation:
According to Mr. Boston, combining whiskey, kirschwasser, cynar, and amaro is grounds for a Boulevardier cocktail. The Boulevardier is a classic cocktail that is similar to a Negroni, but with whiskey instead of gin. It is made by mixing equal parts of whiskey, kirschwasser, cynar, and amaro, and is typically garnished with a twist of orange peel.