Put the melon seeds or pine nuts, poppy seeds, almonds, pistachios, cardamom, fennel seeds and peppercorns in a small bowl. Pour over enough boiling water to submerge everything, then cover the bowl and leave it at room temperature to soften overnight.

Pour the milk into a medium pan and add the spiced nut mixture along with the soaking water. Bring to a boil over a medium heat, stirring occasionally, then simmer over a low heat, uncovered, for 10 mins. Take the pan off the heat, stir in the sugar and saffron strands along with the milk they were soaked in.

Leave to cool until lukewarm, then blitz using a blender until smooth. Strain the milk through a double-layer of muslin into a jug and add the rosewater to taste. Chill the thandai, then pour into small glasses and sprinkle over dried rose petals, if you like.