TO SERVE Make this to order. In a food processor, blitz the pistachios into a fine dust, then tip on to a plate. Crush the cardamom pods in a pestle and mortar and remove the outer shells, then pound the seeds until fine and put in the processor with the mango and mint leaves. Blitz together. With the processor still running, add the yoghurt and squeeze in the lime juice. Now, while it’s still frozen and scoopable, gently roll spoonfuls of mixture in the pistachio dust and serve right away. Finish with a grating or shaving of chocolate.