Peel the skin, cut pumpkin into pieces and cook until they are soft. Mash and keep aside. Add 1 tbsp oil in hot pan, add cumin seeds, chopped green chillies, pinch of hing and turmeric. Sauté and add freshly ground coconut, mashed pumpkin, salt, sugar and mix well. Switch off the flame. Allow this mixture to come to room temperature and then add 1 cup beaten yoghurt and mix well.