Grind together fresh coconut, melon seeds or cashews and fennel seeds in a blender. If you don't have fresh coconut use frozen coconut or dry coconut.
Grind this mixture to a smooth paste by adding some water. If you are using frozen or dry coconut, grind the mixture using hot water.
Heat oil in a pot or pressure cooker. Add in fennel seeds, cinnamon, cardamom and cloves. Fry them for 30 seconds till fragrant.
Add in sliced onions and saute for couple of minutes till onions turn translucent.
Add in ginger garlic paste and green chillies and saute for 1 more minute.
Now add in turmeric powder, peeled chopped potatoes and salt. Stir fry everything for 2 mins.
Add salt to taste and pour enough water to cover the potatoes. Bring it to a boil and pressure cook for 4 whistle. If you are cooking this in a regular pot, then cover and cook on a low flame for 25 to 30 minutes.
Now let the pressure release naturally on the cooker, add in the ground coconut melon paste and mix well. Simmer for 5 more minutes or cook until the kurma thickens.
Serve this with roti, appam, idiyappam.