Scrape the mango skin, grate them and keep aside; alternatively, chop the mangoes fine. Roast the fenugreek seeds until they turn dark brown, grind into a fine powder and keep aside. Heat oil in a sauce pan and add mustard. When the mustard crackles add the grated mangoes, turmeric powder, salt to taste; add some more oil and stir the ingredients all the time. When the mango is done to turn and all the ingredients in the frying pan are reduced to a soft, smooth mass, which no longer sticks to the sides or bottom of the sauce pan, add the chilli powder and mix well with the soft smooth mass. Add powdered fenugreek seeds, asafoetida powder and some more oil amd mix well. Shut off the flame as soon as the chilli powder, fenugreek seeds and asafoetida are assimilated with the soft, smooth mass.