Wash the sweet potatoes thoroughly and steam cook. Once done, peel off the skin. Now grind the pulp in a mixer grinder without water, fine, as to get a soft and smooth paste.
Then, empty the ground mixture into a wide mouthed vessel, oil your hands and knead the paste, with all the above mentioned ingredients except oil into a soft dough. Now make small lemon sized balls.
Then press or roll these small balls in between two slightly oiled, stiff plastic sheets, into thin rounds, with the help of a rolling pin.
Do not lift these rolled out rounds, with bare hands. Just place them onto the sheet or mat, that would be used to dry these papads on and remove the plastic slowly, once the rolled round is placed on that sheet.
Allow it to sun dry for minimum two days (Best under the scorching sun). Then collect them and store in an airtight container, to be used for days to come.
Deep fry them as and when needed. For those who are oil conscious, you can just place them in the microwave for 30 seconds and enjoy them oil free.