Bring milk to a boil in a small pan over moderate heat. In a blender or food processor using the low setting, combine egg, 2 tablespoons of sugar, espresso powder, salt, semisweet chips and whiskey. With the machine off, add boiling milk in a slow stream—the hot milk will cook the egg and melt the chocolate. Process or blend 1 minute, until smooth. Spoon into teacups or champagne glasses, and chill.
When ready to serve, whip cream until soft peaks form, about 1-2 minutes. Sprinkle in remaining tablespoon of sugar and combine.