Heat the ghee in a broad non-stick pan, add the lotus seeds, and sauté on a medium flame for 3 to 4 minutes or till they turn crisp. Remove from the flame, allow it to cool and blend in a mixer to a coarse powder. Keep aside.
Boil the milk in a deep non-stick pan, add the sugar, mix well, and cook on a high flame for 2 minutes or until the sugar dissolves while stirring continuously.
Reduce the flame to medium, add the coarsely crushed lotus seeds, mix well, and cook for 19 minutes or till the milk has reduced to half, while stirring and scraping the sides of the pan occasionally.
Add the saffron strands and nutmeg powder, mix well, and cook on a medium flame for 1 more minute.
Switch off the flame and mix well and allow to cool completely. Add Groviva® powder, stir and mix well. Refrigerate for at least 1 hour and serve chilled garnished with pistachios.