Soak dry tamarind in 1/4 cup of water.
Defrost coconut if using frozen.
Wash and slice bitter gourd in half.
Remove the seeds as they may be hard to chew on.
Chop bitter gourd into tiny pieces.
Heat a heavy bottomed pan, on medium to high heat. Add oil.
Add mustard seeds, de-husked black gram, broken dry red chillies into the oil.
When mustard splutters and black gram turns golden, add curry leaves and chopped bitter melon.
Add turmeric powder and salt. Cover and let bitter melon cook on medium heat. Stir occasionally.
When bitter melon is 90% cooked, add jaggery, tamarind water and red chilli powder .NOTE: Squeeze the tamarind, to help release it's pulp into the water. Discard the fibrous parts. Mix and simmer on low-medium heat for five minutes. It is important to simmer for five minutes to help deepen the flavours of jaggery and tamarind and for the raw flavours to go away.
Add grated fresh/frozen coconut and stir. Cover and simmer for a minute.
Turn off the heat. Serve with rice + ghee/yogurt. Can also be served with jowar/bajra/whole wheat rotis.