In a blender, add all the ingredients mentioned under "Grinding Section" ,add some water and blend to make a smooth paste.
In a kadai, heat oil over medium flame. Add mustard seeds, hing and when they splutter, add curry leaves.Then add raw mango paste.
Cook over a medium flame for about 6 to 8 minutes, stirring in between to prevent the blackening and the sticking of mango mixture to the vessel.Add water for desired chutney consistency. Saute till chutney changes its color.
Cool and serve with steamed rice, chapati or dosa.
Notes
Can be stored upto 2 weeks in the refrigerator.
I have used one medium mango for this chutney as it was not that sour. So adjust the mango quantity based on your taste and the sourness of mango
Note: Nutrition values are my best estimates. If you rely on them for your diet, use your preferred nutrition calculator.