Mixologists John Gertsen and Misty Kalkofen of Drink in Boston created this sweet, slightly grainy punch. When the milk curdles, says David Wondrich, "it will produce a truly revolting-looking mass." Strain the punch through a very-fine-mesh strainer or, even better, through cheesecloth or a clean white T-shirt. Chill thoroughly before serving as a great, potent after-dinner drink.
In a large pitcher, stir the ground coffee with the milk and refrigerate for 24 hours. Pour the coffee milk through a fine strainer into a large saucepan and warm over moderate heat; keep warm.
In a large bowl, stir the sugar with the lemon juice until the sugar dissolves. Stir in the rum, Bénédictine, maraschino liqueur and nutmeg. Add the warm milk; the mixture will look curdled. Pour the mixture through a fine strainer into a punch bowl and let cool, then refrigerate until chilled, about 2 hours. Add ice.