In a saucepan over medium heat, bring sugar, cocoa, cream, water, butter, and salt to a boil, stirring constantly. Let boil three minutes, constantly stirring. Remove from heat.

Let cool 30 minutes. Beat powdered sugar, vanilla, and orange liqueur into chocolate mixture until frosting reaches thick but spreadable consistency. If frosting is too dry, add milk ½ teaspoon at a time. if frosting is too runny, add powdered sugar, 2 tablespoons at a time. Frost cupcakes. If full cupcake coverage is desired, double amounts for frosting ingredients.