Here is an excerpt:
"While each region has its specialty, fufu transcends regional boundaries in Ghana. Fufu consists of a gooey ball of pounded vegetables sitting in a bowl of one of three main soups.
In the south of Ghana the fufu tends to be made from boiled and pounded cassava and plantain, whereas in Tamale and further north, fufu is made from pounded yam alone. After boiling, the vegetables are pounded in a large wooden mortar with a four foot long wooden pole as a pestle. One or two people hold the pole and pound, while one person crouches by the bowl and turns the sticky ball, defying the threat of a broken hand every time the pole comes thudding down.
Food by Country describes fufu thus: "A staple throughout West Africa, including Ghana, is fufu (boiled plantain, cassava, or rice that is pounded with a large mortar and pestle into a round ball)."
Unlike the small, orange or purplish vegetable known by most North Americans as yam, Ghanaian yams are white on the inside and brown and woody on the outside. They are approximately 16 to 20 inches long and weigh more than three pounds, on average."