Step by step recipe:

1. 5 min.
   Soak 2 sheets gelatin in cold water for 5 minutes to soften.
2. 7 min.
   Pour 250 ml liquid cream into a saucepan on medium heat and bring to the boil.
3. 3 min.
   Add 50 g Pistachio powder or paste and whisk until thoroughly mixed.
4. 30 min.
   Next add the softened gelatin (after draining well).
   
   Mix until fully melted, then leave the mixture at room temperature to cool for about 30 minutes.
5. 2 hours
   Lay a tea towel on a baking sheet and stand the small glasses on this (to stop them sliding about).
   
   Divide the mixture between the glasses, then refrigerate for at least 2 hours.
6. 5 min.
   Meanwhile, put 60 g pistachios in a small frying pan on high heat and toast for about 5 minutes (they should only colour slightly).
7. 4 min.
   Add 40 g caster sugar to the pan and caramelise the pistachios.
8. 5 min.
   When they are well caramelised, tip the nuts out onto the worktop (or onto a sheet of cooking parchment if you prefer) to cool.
9. 2 min.
   When cold, chop coarsely with a knife.
10. 6 min.
    When you are ready to serve, take the panna cotta out of the fridge and add a little custard to each glass.
11. 5 min.
    Finish with a few chopped caramelised pistachios and serve.