In a wok or saucepan that has a heavy bottom, add 1 tbsp of sesame oil. When the oil is hot, add in the mustard seeds. Sesame oil becomes frothy, which is normal, and then the mustard seeds will sputter.
Then, add the mustard seed powder, asafoetida and fenugreek powder and mix well — Cook for about 20 to 30 seconds over medium-low heat.
Reduce the heat to low and add the grated raw mango, salt, turmeric powder, and red chili powder.
Mix it thoroughly and cook for 10 minutes over medium-low heat. Keep stirring for every two minutes.
Now taste the pickle and add more salt or red chili powder, and also 2 tbsp of oil. I added ½ more tsp salt and 1 tsp red chili powder.
Mix it thoroughly and cook again for 10 minutes over medium-low heat. Keep stirring for every two minutes. At this stage, you can see oil oozing a little around the edges, and also the pickle will be shiny/glossy.
Now add the remaining 1 tbsp of oil and mix.
Cook again for 5 to 7 minutes over medium-low heat and then turn off the heat.
Allow the pickle to cool thoroughly and then store it in an air-tight container. This pickle stays good for up to 10 days when refrigerated.
I did not peel the skin of the raw mango. I grated it along with the flesh. But you can remove the peel and grate.
Adjust the salt and spice according to your preference and also depending upon the sourness of the mango.
If your raw mango is very sour, you might have to add more salt and red chili powder. When I say more, it means a tsp or two more.
If your mango is not sour, then you might have to cut down on the salt and red chili powder. If it's on the sweeter side, then you can add more fenugreek powder as well.
I used sesame oil for this recipe. You can use vegetable or corn oil or oil of your choice.
I used only 4 tbsp of oil. But for this measure, you can add 6 to 8 tbsps of oil.