Roast the yam on the fire, so that the root hairs of the yam will be roasted off. Clean the baked yam and remove the inedible parts. Cut the yam into sections and put it in a steamer. Put it on a steamer or rice cooker and steam for about 15 minutes after exhausting. The most convenient way to judge whether yam is steamed is to poke it with chopsticks. Yam contains a lot of starch, so it will soften when cooked, and chopsticks have no hardness when cooked.