Add hot milk to the crushed saffron, mix well, and set aside for 10 minutes.
Add whipping cream and icing sugar (if using) in a sufficiently large bowl.
Beat at medium speed until the cream thickens.
Add the saffron-infused milk, continue beating at high speed until stiff peaks form.
To check: Tip the bowl upside down, if the whipped cream doesn't move, it is done
Transfer the cream to a piping bag fitted with a star nozzle. This is an optional step but makes for a pretty presentation.
Crumble the ladoos in a bowl. Set aside.
Place a layer of crushed motichoor ladoo at the bottom of the serving glass or bowl.
Top with the saffron whipped cream.
Repeat to add another layer each of crushed ladoo and the cream.
Garnish with slivered pistachios.
Repeat to make more parfaits.
Refrigerate for a few hours until ready to serve.