Cut mangoes into small pieces. mix with green chilly, kayam, salt to it keep it for 5-6 hours
After six hours slowly separate water which was obtained from mango mix to another vessel. In this water add chilly powder, salt and mix it.
Heat pan, add oil and mustard. after that add water mix(chilly powder+salt) become heat. after that turn off stove. mix the mangoes with it. mango pickle ready