Add milk, semolina, sugar and ghee in a broad wide non stick pan.
Switch on the gas now and keep the flame on high at first.
As soon as the mix starts bubbling, lower the flame and continue cooking by constant stirring.
This is an important step to follow.
It starts leaving the sides off the pan after about 25 minutes of constant stirring. At this stage, add the food colour if using and mix well.
When the halwa starts leaving the sides of the pan fully, take it out onto a butterpaper.
While it is still hot, cover it up with an another butterpaper and start rolling.
Roll it vertically from top to bottom and do not forget to take a big sheet of butterpaper so that it is easy to roll.
After rolling, sprinkle the cardamom powder and nuts on top.
Roll again keeping the butterpaper sheet on top to nicely press down the nuts.
Carefully lift the butterpaper now and keep it refrigerated for about 4 hours.
Cool cool melt in mouth ice halwa of Mahim, Mumbai is ready to be served chilled.
Slice it before serving with the butterpaper sheet on.