Stir all of the ingredients with ice, then strain into a chilled coupette or Nick & Nora.
2.
Optionally, express a lemon and orange twist over the finished cocktail, then use as a garnish.
Notes
A bit of history
This drink first appeared in 1892's "The Flowing Bowl" by William Schmidt, then largely disappeared. A similar recipe, for the absinthe-free Bonsoni Cocktail, appeared in 1917 in Hugo Ensslin’s "Recipes for Mixed Drinks."
On the garnish
Schmidt didn’t specify a garnish for the drink in his 1892 book, but Yarm (who adapted the original to this recipe) says a lemon twist “would smooth out the fernet’s aggression, and an orange twist to sweeten things would be nice, too."