Boil potatoes till done and let them cool down slightly.
Peel the potatoes and chop into medium size cubes.(Don't make very small pieces of potato else they get mashed while roasting)
Chop green chilies and ginger into small pieces( quantity of green chilies can be adjusted as per your preference )
Heat oil in a heavy bottom pan. when it become medium hot add mustard and cumin seeds and let them crackle.(you can also add 1/4 tsp whilte lentil/ urad daal )
Now add asafoetida and chopped green chili, ginger and curry leaves and give a nice stir for few seconds.
Now add turmeric in the pan and stir to mix.
Add the chopped potatoes and mix in the tempering and stir well.
let it roast for 2-3 minutes on medium heat , spread the potatoes in the pan so they get a nice golden colour.
Now add salt to taste and mix and again let them roast for 2-3 minutes on medium heat.
Now the potatoes are roasted well . Add a pinch of sugar in the potatoes but its optional.
Add lemon juice and chopped coriander and mix well.
Switch off the flame , potato bhaji/ Batata bhaji is ready to serve now.
Enjoy this delicious aloo bhaji with poori, paratha ,or serve with dosa or use as a sandwich filling !