1. Boil the milk in a large, thick-bottomed kadai till it thickens slightly. Add the alum (phitkari) to the thickened milk and stir continuously till the milk becomes grainy.
2. Cook till most of the moisture evaporates and a solid mass remains. Add the sugar and mix well. Cook for five or ten minutes longer till the mixture thickens again. Grease an aluminium tray with ghee.
3. Pour the milk mixture into the tray and level the surface. Sprinkle the sliced pistachios on top. Leave to set for a few hours in a cool, dry place.
4. When completely set, decorate with silver varq and cut into squares or diamonds.