Pavakka Curry/ Biitergourd with Yogurt

I am hoping to entice the guests at the Weekend Herb Blogging, the event created by Kalyn's Kitchen, to go beyond the norm and try South Indian food. This week of WHB is hosted by Ruth at Once Upon a Feast.
Bitter gourds are very popular in Asia and most people either like it immensely or dislike it unreasonably. As you can see, I fall into the former category, hoarding bitter gourd recipes in every form and taste. Bitter gourd or bitter melon is highly regarded for its medicinal properties in Asia but is slow in getting recognition in the Western World.
This curry made with bitter gourd, yogurt and coconut milk tastes best with rice with a stir fried vegetable and fried fish on the side.
You will need:
Bitter gourd- 2 big ones.
Green Chilies- 5 vertically slit
Tomato- 1 small one cut into 4 pieces
Onion- 1 small one sliced
Red chili powder-3/4 tsp
Turmeric- 1/4 tsp
Coriander Powder(Dhania)-1tsp
Coconut Milk Powder- 5 tbsp mixed with 1 cup water (or 1 cup coconut milk)
Yogurt- 1cup
Salt to taste
Oil- 2 tbsp
For seasoning:
Mustard seeds- 1/2 tsp
Cumin (Jeera)-1tsp
Curry leaves- 1 sprig
Canola oil-1 tbsp
Preparation:
1. Scrape the outer projections on the bittegourd and slice the bitter gourd into thin rounds. Sprinkle with ½ tsp salt and 1 tbsp yogurt and let it sweat for 10 minutes. Squeeze the pieces and wash them well to remove extra salt and the bitterness. If you like the bitterness, skip this step. If you are using Chinese bittter gourd or bitter melon, which is light green and bulbous in shape, it is not as bitter so you can directly fry it.
2. Heat 2 tbsp of oil and shallow fry the bitter gourd rounds on medium heat till slightly crisp. Not very crisp. Then add the onions and green chilies and sauté for a couple of minutes.
3. Lower the heat and add the chili powder, coriander powder, turmeric and 1 tablespoon water. Fry for a while till the powders get cooked and then add the tomato and salt. Cook for a minute and add ½ cup water and 1 cup coconut milk. If the coconut milk is thin, then reduce the quantity of water. Vary the quantity of chili powder and green chilies as per taste. My recipes tend to be on the slightly spicier side, so be warned.
4. Check the salt and liquidity of the curry and add more salt and water if needed. Take it off the flame and do not let it come to a full boil. After it cools down, add 1 cup beaten yogurt.
5. Tempering: Heat the oil in a small wok/pan and as it heats up, add mustard seeds and cover till it tops sputtering.Reduce the heat and add the curry leaves and cumin. Pour the flavored oil over the curry.
Serve with hot steamed white rice.