This variation on the Manhattan is a nod to the city of San Francisco and its beatnik culture. Averna (a bitter Italian liqueur) is popular in North Beach, the Italian neighborhood where writer Jack Kerouac was known to enjoy a drink.
In a pitcher, combine all of the ingredients except ice and the orange twists and stir well. Add ice and stir again, then strain into chilled martini glasses. Pinch an orange twist over each glass, rub around the rim and add to the drink.