Boil or steam the cauliflower until just soft, then rinse and drain under cold water to stop it cooking. Blitz the cauliflower with all of the popsicle ingredients in a high speed blender until smooth. Pour into moulds and freeze until solid.

Alternatively, puree the cauliflower with a hand blender until smooth, melt the chocolate and add, along with the other ingredients, and puree until smooth. Pour into moulds and freeze until solid.

To decorate, melt the chocolate and set aside to cool very slightly. Whiz the pistachios in a high speed blender, or in a food mill or coffee grinder, until fine. Dip the frozen popsicles into the melted chocolate and sprinkle with the pistachio dust.