Add in the grated carrots and milk in the inner pot. Stir well. Secure the lid on the pot and close the pressure-release valve. Select manual and cook at high pressure for 3 minutes.
Once the cooking is complete, use natural pressure release to depressurize. Open the lid.
Select saute and adjust to normal. Next add Khoa, sugar, almonds, pistachios, ghee, and ground cardamom.
Stir well. Let it saute until the water liquid evaporates and it becomes completely dry. It should take about 5 minutes. Keep stirring in order to prevent the halwa from sticking to the bottom of the pot.
Finally, transfer the halwa in a serving bowl and garnish with additional nuts if you like. Serve hot or at room temperature, whatever you prefer.