Boil the potatoes, peel and cut into tiny cubes.
In a saucepan heat 3 tbsp oil and add the mustard seeds.
When they sputter, add the black dhal and cashew nuts.
When the dhal and nuts turn a golden brown, add turmeric powder, finely-chopped onions, green chilies, ginger and curry leaves and stir for a while.
When onions are well cooked add the potatoes and salt.
After a minute or two remove from heat, add lemon juice and stir well.
Make small balls out of the mixture (about 25-30 balls) and keep aside.
Make a thick batter from gram flour, about 1/4 pint water, chili powder and salt.
Heat oil in a deep-frying pan.
Gentle dip the potato balls one by one in the batter, making certain that all the sides are evenly covered.
Then drop them carefully into the smoking oil. About 4-5 bondas can be fried at a time.
Keep turning them constantly and when they are a golden brown, remove from oil and drain.
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