5medium potatoes(boiled in their jackets and diced. You don't have to peel the potatoes if organic. Russets or yellor or red potatoes are all fine--russets will mash more easily and will become crustier)
1mediumonion, finely diced
2green chili peppers(like jalapeno or serrano, minced)
Add the cumin seeds and asafetida. When the seeds sputter, add the onions and curry leaves and green chillies and saute until the onion turns transparent, about five minutes on medium heat.
Add the ginger and turmeric and saute a few more seconds. Add the potatoes and stir them in to combine with the oil and spices.
Mash down the potatoes with a potato masher or a heavy ladle so some of the pieces break up but others remain mostly intact. You want the potatoes to start turning slightly golden and crusty at the bottom of the pan.
Add salt and lemon juice and mix well. Garnish with the coriander seeds or, if you like, some grated coconut.
Nutrition info is for the potato bhaji and doesn't include the pooris.