Cut open the vanilla pod.
Soak the gelatine for 10 minutes in cold water. Remove the vanilla pod from the water, using a knife, scrape the seeds from the pod and stir into the cream.
Bring the cream, the sugar and the vanilla pod to the simmer.
Squeeze the water from the gelatine and stir the gelatine into the hot cream that has been removed from the heat source.
Stir in the finely chopped pistachio nuts, keeping some separate for the garnish.
Pour the cream mixture into four coffee cups that have been rinsed in cold water.
Leave the panna cotta in the refrigerator for at least 1/2 day to become completely firm.
Empty the panna cottas into the middle of a plate.
Garnish by sprinkling the remaining nuts over the panna cottas.