Dry roast the ragi flour for a few minutes, sieve together the ragi flour and gram flour, take them in a large bowl.
Now add the butter, mashed potatoes, sesame seeds, red chilly powder to the flours and knead the flour with enough water as a smooth dough.
Heat the oil for deep frying and take a ball of dough, put in the muruku press. Squeeze out the murukku over a greased plate and drop gently in hot oil, fry until the oil stops bubbling.
Drain the excess of oil in a paper towel. Conserve in an air tight box.
This murukkus stays crunchy even after two weeks.