This is a traditional south indian dish called majjige huli or majjige palidha in Kannada and Moru kozhambu in Tamil. As the name says, this gravy is a mixture of ground coconut and buttermilk (majjige), spiced with green chillies and flavoured with cumin that is added to the vegetable. I have used winter melon which is called vellai pooshani kaai in tamil. There are different versions of preparing Majjige huli and this is my mom's recipe.
Winter melon - 2 cups - diced into 1 inch cubes
Grind together the following:
Grated fresh coconut - half cup
Heat oil in a kadai and add the mustard seeds, when it pops, add the urud dal. When it turns light brown, add the diced winter melon, curry leaves, asafoetida powder and salt. Stir for few seconds and add one or one and half cups of water. Let it boil until the vegetable is cooked.
Meanwhile, add turmeric powder to the buttermilk and mix well. Keep it aside.
When the vegetable is cooked, add the ground coconut masala and mix well.
When it starts bubbling, reduce the heat and add the buttermilk.
Wait for just one boil and remove from heat.
This can be done using different vegetables:
Potato: Follow the same recipe, substitute potato in the place of winter melon.
Okra/ladies finger - cut into 1 inch length: Instead of adding water to cook, roast the okra.
You can substitute with other vegetables of your choice but winter melon and okra & potato are the popular vegetables for this majjige huli.
Serve with white rice. Enjoy with a spicy roasted vegetable or pappad.