He made it sound like his yams aren't that tasty, I guess it depends a lot on the strain and growing conditions.
Boiled, roasted (as mentioned), as a porridge, fried and pounded.
Boiled - Cut, salted (some add sugar)boiled and eaten with sauce, palm oil, beans...
Pounded - Boiled unsalted yams are pounded into dough form and eaten with soup. It's called pounded yam.