Pound half of the litchis gently with a light pestle. Finely chop the remaining ones.
Set the milk to boil in a thick bottomed pan, add the green cardamom powder and let the milk simmer lazily over a low flame till it has reduced to almost one third of its volume.
Switch off the flame . Let the milk cook down, some 5-7 mins I would say.
Add the litchis. Give it all a loving stir.
Add sugar to taste. (The litchis I used were very sweet and just a tablespoon of sugar was enough for me)
Another hearty stir and we are done. Allow to cool to room temperature, then refrigerate for 6-8 hours.
Serve chilled .
