Mix water and balsamic in a bowl and chill in refrigerator for at least an hour.
Once the mixture has thoroughly chilled, freeze in your ice cream maker according to the manufacturer’s instructions. (If you don’t have an ice cream maker, you can pour the mixture into a shallow pan and freeze in your freezer until semi-solid. Then take a fork and fluff it up, returning it to the freezer to freeze firm. Then put in a food-processor or blender to process until smooth.)
Place sorbet in an airtight container and freeze until ready to serve.
Serve with a garnish of mint as a palette cleanser between courses or as a refreshing dessert.