It is jokingly nicknamed 'face the wall', from the idea that people once ate this cheap, dark swallow facing the wall so neighbours wouldn't see what they were eating.
Cassava chips are sun-dried, then pounded into a coarse flour that's stirred into boiling water until it forms a smooth, grey-brown dough. It's served in a bowl with a soup — light soup, palm-nut, or groundnut — same as fufu.