Add ghee to the Instant pot. Once hot, add cashews, and coconut pieces. Fry till light golden brown. Remove from the pot and keep it aside.
In the same ghee, roast the moong dal till a flavourful aroma comes. Don't let it brown too much.
Remove the dal from the pot, and wash it well. Drain the water and add the roasted moong dal back to the pot.
Add 2 cups of water. Close the Instant Pot and ensure the pressure valve is in Sealing Position. Cook on High Pressure for 10 minutes.
Once cooking is done and the Instant Pot beeps, let the pressure release naturally.
While the moong dal is cooking, soak 1 tbsp rice and 5 cashews in a little bit of warm water for 10 minutes.
Grind the soaked rice, cashews, grated coconut and cardamom to a fine paste.
Once pressure releases naturally, Open the lid of the Instant Pot, and mash the dal gently.
On saute mode, add the jaggery to the cooked dal and mix well. Add the coconut paste and let it come to a gentle boil. Add milk. Let the payasam cook for 5 minutes. Switch off.
Add the ghee roasted cashews and coconut pieces on top. Serve the moong dal hot or cold.