West and Central African tables know fufu as the smooth, elastic staple pounded from cassava, though taro, yams and cocoyams serve the same role. The plain version starts with boiling or steaming the tubers, then pounding them, singly or mixed, into a dough; the fermented version soaks the roots for three to four days first, then forms them into pastes. Diners pinch off pieces to scoop up saucy stews. In some areas it is sold ready-made as a convenience food. Hygienic water and thorough cooking matter, since cassava carries cyanogenic compounds that processing must remove.