"This is like a really fine chocolate truffle that melts in your mouth," says bartender Marvin Allen. He makes this variation on a chocolate martini with nocino, a walnut liqueur produced in Modena, Italy.
Fill a cocktail shaker with ice. Add all of the remaining ingredients except the chocolate shavings and berries; shake well. Strain into a chilled martini glass. Garnish with the chocolate and berries.