Finely grate carrots using a grater or a food processor. You can grate them very fine or keep them semi-thick.
Add ghee or butter to a thick bottomed pan and once it melts, add the grated carrots. Roast the carrots on low-medium flame till they turn light golden.
This could take around 7-8 minutes. Then stir in the milk and cream, and bring it to a boil. Keep the flame on medium. Add orange food color at this point if you want.
Now add condensed milk, and stir it in. Cook for 8-10 minutes or till the carrots become soft and are well blended in milk.
Then, add the chopped nuts, cardamom powder, and saffron.
It should be a thick flowing mixture like kheer.
Transfer it to a bowl when done. Let it come to room temperature
Refrigerate the carrot halwa mixture and freeze the ice cream base, overnight to get the best ice-cream.
Then, pour this mixture into the frozen base of the ice cream maker and churn it as per the maker's instructions. This could take 15-20 minutes.
Once it's done, immediately transfer it to an ice cream container. Place a lid and freeze the carrot halwa ice cream overnight.
Prior to serving, let the container sit on your counter (out of the refrigerator) for about 10 minutes
Then, add one, two, or even three scoops of carrot halwa ice cream in a bowl, garnish with some chopped nuts and saffron strands and serve.