Cook mango in a pan with little water, salt and turmeric powder
Dry roast channa dhal, coriander seeds, cumin seeds, dry red chili (reserve 1 for tempering), fenugreek, black pepper, allow it to cool
Grind the above dry roasted ingredients along with coconut and ginger into thick paste
When mango is tender add the ground paste and mix well
Add curd and mix well
Add water to get required consistency, mix well and bring to a boil
Add jaggery and mix well until it completely dissolves
Heat oil in a pan
Add mustard and allow it to splutter
Add asafoetida, dry red chili after making them into pieces and fry
Pour into the kootan
Serve hot with rice or adai