Peel your raw mango and then cut into large chunks. For the seed of the mango, leave some flesh on so you can use it too.
Grind together the coconut, red chillies and turmeric powder with water until you have a creamy sauce base. The consistency should be smooth, very mild grains of coconut (if any) and not watery at all.
In a pot, add coconut oil and temper it with mustard seeds and asafoteida(heeng) just until you here a sizzle. Add the raw mango and let it coat evenly in the oil.
Add about 1/2 cup of hot water to the raw mango along with the jaggery and salt. Cover and cook until a couple of mins away from being fork-tender on medium to low heat.
Add the coconut sauce, mix through and cover to let it it cook for a minute on low heat. Then taste and adjust the seasoning. The curry should have fine balance of heat, sourness and sweetness. Once seasoned, cover and cook for another minute or so and then turn off the flame. Let it rest for atleast 10-15 minutes before serving/eating