Heat 250ml water in a pan until boiling, then stir in the sugar and food colouring, if using.

Remove the seeds from the cardamom pods and discard, then add 3 of the cardamom husks to the pan. Boil for several minutes, then transfer to a heatproof jug or bowl.

Heat the ghee in the same pan, then add the remaining cardamom husks and the pistachios. Fry for 1 min, then add the semolina. Toast for a few minutes, stirring frequently to prevent burning. Return the hot sugar syrup to the pan, stirring continuously to avoid clumping until all the liquid has been absorbed. The cooked halwa should mould together easily. Scoop out the cardamom husks and serve hot with puris or parathas, if you like.