Not only Henan yams are truly good yams, Henan Tiebang yam is just a registered trademark and has become particularly famous after vigorous publicity. Tiebang yam is cultivated in large areas and sold all over the country, so it is particularly famous. In fact, the real good yam is not cooked crispy, but powdery. Which kind of black-skinned yam is the best, although it doesn’t look good. I have been looking for this kind of yam on the Internet. Later, I saw this kind of wild skin yam in the "Selling is Health" store on Taobao. It is the best yam. However, the store sells dried ones. She said that the fresh ones cannot be transported and they are wild. There are not many of them, so they can only sell dried ones. I specially bought a pound, and when I came back, I saw that it was quite white, because only black-skinned yams are dry when dried, while iron-barked yams are black when dried. There is no sour taste when drinking the soup, it feels good.