Heat oil in a wok or deep saucepan on medium heat. When the oil is well heated, add mustard seeds. Wait until the seeds start to splutter, then, add the cumin and fenugreek seeds. About 20 seconds.
Stir the seeds, and then add whole green chili or red chili powder (optional). If you like it chili hot, chop the green chili in half or dice them.
Add onions and sauté till half brown, about 7-8 minutes.
Add tomato paste, kaddu, salt and half of the cilantro. Stir till the tomato paste to coat the pumpkin evenly. Cover and cook on low until half cooked, approximated 5-7 minutes.
Uncover and cook, stirring occasionally, until the pumpkin is tender and starts to brown a little, approximately 5-6 minutes. At this stage, slightly mash it with the back of a cooking spoon to get a chunky texture. Drizzle some oil along the edges of the sabzi. Stir a couple of times, making sure to scrape from the bottom.
Spoon into a serving dish. Serve garnished with sautéed peanuts or cocktail peanuts and the rest of the chopped coriander.
Goes well with roti and, of course, plain rice and dal.