Dry roast peanuts and sesame seeds separately till the nutty aroma wafts out. You can use small seasoning pan for this purpose.
Next transfer the roasted ingredients to the mixer and get them coarsely powdered. Also soak the tamarind in half cup of water for about 10 mins.
Next step is to grind the coconut, coriander leaves, cumin, ginger and green chillies together to fine puree including water as needed. Take this puree in a wide bowl along with powdered peanut plus sesame, salt, onion, turmeric powder, tamarind water, jaggery and sambar powder. Combine everything together. Stuffing mixture is ready.
Wash the ridge gourd well with enough water. Trim the edges and remove the hard ridges using a sharp knife. Next cut the ridge gourd at every 1.5" length and slit each part in to half and quarter as shown below. Keep the base intact and do not cut them in to pieces. Now carefully fill the stuffing masala in to slit ridgegourd and keep them ready.
Next heat a pan adding oil, mustard seeds and crushed garlic. When mustard seeds sizzle, add all the stuffed ridgegourds and let it cook for 2 to 3 minutes. Pour the remaining stuffing mixture and a cup of water. Cover it with lid and cook in simmer until ridge gourds are soft. Stir and flip in between for even cooking.
Very very delicious stuffed ridgegourd is ready to serve with chapati or jolada rotti.