In a large saucepan, bring water to a boil. Remove from the heat; stir in the coffee. Add marshmallows; cook for 5-6 minutes over low heat until marshmallows are melted, stirring occasionally. Pour into a large bowl; cover and refrigerate until slightly thickened.
In a small mixing bowl, beat cream until soft peaks form; fold into marshmallow mixture. Spoon into dessert dishes. Garnish with whipped cream and additional coffee granules, if desired.