Scrub the carrots with a vegetable brush and peel them.
Using a hand grater or food processor, grate the carrots.
Transfer the grated carrots, milk, and whipping cream into a heavy-bottomed medium-sized pot. Bring to a boil on medium heat. About 10 minutes.
Add the whole cardamom and cardamom powder. Simmer on medium-low, occasionally stirring, until 75% of the milk is reduced. About 20 minutes.
Add the sugar and golden raisins. Stir in half the nuts. Cook for another 10 minutes until most of the liquid has evaporated, but the halwa is still moist.
Carefully transfer the cooked dessert to a serving dish and garnish with the rest of the nuts. Serve hot or warm.