Prepare 500 ml strong coffee. Scrape out half a vanilla pod and stir the pulp, sugar and STROH rum into the coffee. Pour the rum and coffee mixture into a wide bowl and freeze for three to four hours. Keep stirring with the whisk in between so that the ice does not freeze evenly. As soon as a coarse-grained sorbet has formed (after about three hours), stir with a fork and pour into glasses. Pour whipped cream or, alternatively, whole milk over the granita and enjoy immediately chilled!