Add palm jaggery and 1 tbsp water to a pan. Heat until melted. Strain the jaggery syrup to remove impurities and keep aside.
Dry roast moong dal until the color slightly changes and aroma comes. Cool completely and grind into a fine powder.
Add sliced coconut, moong dal powder, and ¼ cup water into a mixer. Grind coarsely (about 90% ground, not a fine paste).
Heat 1 tbsp ghee in a pan and roast cashew nuts until golden. Keep aside.
In the same pan, add the ground coconut mixture. Add ¼ cup water and cook for about 5 minutes until the water evaporates. this step removes the raw smell of coconut
Pour the strained jaggery syrup into the coconut mixture and stir continuously.
Add ghee little by little while stirring continuously until the mixture thickens to a halwa consistency.
Add roasted cashews and cardamom powder. Mix well and switch off the flame.
Transfer to a bowl and serve warm