(1) Brew the espresso, add sugar, and stir until dissolved. Stir in whiskey and pour into a freezer safe baking dish.
(2) Let freeze uncovered for two hours, then scrape/break up the ice crystals with a fork. Cover and let freeze completely, another two hours or overnight.
(3) Fluff the ice crystals with a fork again before serving. Spoon into bowls and top with lightly whipped cream.