Rinse and soak tamarind in warm water. Squeeze and filter the thick juice.
Heat oil in a deep pot. Add cumin, mustard and methi. When they begin to splutter, add curry leaves and green chili. Sauté for a min.
Add onions and sprinkle salt. Fry till they turn slightly pink, needs no browning of onions.
Next add the pumpkin pieces, fry on high flame for 2 to 3 mins.
Add red chili powder, turmeric and fry for a min.
Next add jaggery and pour the tamarind juice. Mix, cover and cook on a low flame for 3 to 4 mins. This helps the pumpkin pieces to absorb the flavors.
Add enough water to cover the pumpkin pieces , add coriander powder.
Cover and cook till pumpkin is fully done. Cooking on a very low flame makes the pulusu tasty.
Off the heat and add coriander. Keep gummadikaya pulusu covered until served so it absorbs the flavors. Serve with hot rice and ghee.