It can be cooked in 15 to 20 minutes. Tiegun yam has a hard texture and is rich in starch. Its steaming time is similar to that of root foods such as sweet potatoes and potatoes. It is advisable to steam for 15 to 20 minutes after the water is boiled. If the iron yam is small and the amount is not large, steam it It will be cooked in 10 minutes. On the contrary, if the yam is thick and large, the steaming time will be extended. If you want to steam the iron bar yam quickly, you can steam it in a pressure cooker. Steam it for 5 to 10 minutes and it will be cooked. The simplest method for iron yam is to wash it and steam it directly. Use a dishwashing iron sand ball and water to gently wipe the skin of the yam to remove the hairs and pores. There is no need to use a paring knife to peel the yam. The skin contains one-third of the nutrients, so eating it with the skin is more nutritious.