In a large bowl combine the flours, and all the spices.
Add in the cilantro and slowly add in the water until you have a thick batter. Add more or less water as necessary.
Slice the potatoes using a mandolin or knife
Heat the oil to medium high heat.
Place the potatoes in the batter, coating each piece well on both sides
Put in the hot oil and fry until golden and flip to repeat on other side
Remove from oil and place on a paper towel to remove excess oil
Do this until all the potatoes are cooked.
Serve hot with madras (mango chutney)