Separate the egg whites and the yolks. Whisk the egg whites until it becomes thick. Add a tsp. Of sugar and whisk until it dissolves to the whites.
Whisk the cream separately until peaks formed. Add this to the egg whites. Then add the vanilla essence, cardamom powder and half of the chopped pistachios and mix well. Put this in a plastic container. Close and freeze for about 3 hours. Take it out and put it in a food processor or mixer and process until smooth. Then pour this in the same plastic container again and freeze for another 2 hours. Again take it and process it in a food processor or mixer. Then freeze this until it becomes solid. Sprinkle the remaining pistachios and grated nutmeg on top and serve.