Peel and cut the ash gourd into cubes.Place the ash gourd cubes in a pot with just enough water to cover them.
Add a pinch of salt and the turmeric. Cook on medium heat until the gourd is translucent and fork-tender (about 8–10 minutes). Do not overcook it into a mush!
While the gourd cooks, blend the soaked chana dal and rice, grated coconut, green chilies, ginger, cumin, coriander seeds, and leaves into a very smooth, thick paste. Use as little water as possible.
Add the ground masala paste to the cooked ash gourd. Let it simmer on low heat for 5 minutes so the raw smell of the dal disappears.
Turn the heat to the lowest setting. Slowly pour in the whisked curd or the Indian buttermilk. Stir continuously.
Do not let the mixture come to a rolling boil after adding the curd, or it will curdle. Just heat it until you see tiny bubbles starting to form around the edges.
Heat coconut oil in a small pan. Add mustard seeds, red chilies, curry leaves, and hing. Once they crackle, pour the tempering over the Majjige Huli.
Cover the pot immediately to trap the aroma. Majjige Huli is ready to serve.