Heat ghee in non-stick pan or heavy based pan over medium flame. Add grated carrots and roast them for 3-4 minutes while mixing continuously.
Pour milk over ghee roasted carrots and stir to mix well. Bring it to boil over medium flame.
When it starts to boil, reduce flame to low and cook until almost milk is absorbed and mixture starts to thicken. It will take approx. 15-20 minutes. Stir occasionally in between to prevent sticking.
Cook until all milk is absorbed and mixture turns thick for approx. 5-7 minutes. Stir occasionally in between.
Add sugar, chopped cashew nuts and raisins, mix well. Stir and cook until sugar is dissolved; approx. 3-4 minutes.
Add cardamom powder, mix properly and turn off the flame.
Transfer it to a serving bowl and garnish with sliced almonds and pistachio's.
Tip_1Add 1/4 cup unsweetened khoya (mawa) in step-4 for a nice creamy texture. If you are using sweet khoya, then adjust sugar accordingly.
Tip_2 Make richer, creamier, gajar halwa with condensed milk by adding 1/4 cup sweet condensed milk and reducing sugar to 1 tablespoon.