1. Put milk and cardamom pods in a large heavy-based pan and bring to the boil.
2. Reduce heat to medium-low and simmer, uncovered, stirring frequently, for 30 minutes or until mlik is reduced by about two thirds.
3. Remove cardamom pods with a spoon and discard.
4. Stir in sugar, almonds and half the pistachio nuts and simmer for 5 minutes more. Leave to cool.
5. Pour reduced milk into a plastic container, cover and freeze for 2-3 hours, until frozen around edge.
6. put into a blender and grind until smooth and light.
7. Return to container, cover and freeze for 1 hour.
8. Put 6 individual 3/4 cup moulds into freezer to chill.
9. Put frozen mixture into moulds, pressing down firmly.
10. Cover and freeze for 2-3 hours, until solid.
11. To serve, dip moulds in hot water for a few seconds and turnout onto plates.
Serve at once , sprinkled with remaining pistachio nuts.