Boil the potatoes by adding salt. Peel them and keep aside.
In a thick bottomed pan, heat oil. Once the oil is hot, keep the flame to very low and add cumin.
Once the cumin starts changing colour, ( if you think the oil is too hot, turn off the flame till you add all the ingredients) add salt, turmeric, chilli powder, dry mango powder, roasted cumin powder, roasted turmeric powder and mix well.
Now add the baby potatoes and mix well. Keep tossing till all the potatoes are covered with the spices. Keep tossing for 2 min and add chopped coriander and toss well again.
Transfer the contents to a serving bowl and serve hot with rice-sambar or roti.