Cook potatoes in salted water till it is tender...It will take around 20-30 mins..Drain it and peel the skin off..Set this aside for a moment
In a frying pan heat a tsp of oil..Add in urad dal, pepper and dry red chilli and toast for 5 min or untill golden.Let it cool down then grind it into a fine powder.
In a kadai heat the remaining oil ,Add in the onions and cook for 2 min.
Add in the potatoes and mix well.Season with salt..