In the Shanxi dialect, the word "Banji" is used to refer to potatoes. The origin of the word can be traced back to the appearance of potatoes in the Shanxi dialect, i.e., their shape is flat and hard, similar to a chicken plate. When the people of Shanxi use the word "plate chicken", they are actually referring to potatoes. This is a unique way of using words in the Shanxi dialect, which is not common in other regions. So in Shanxi, when people say "plate chicken", they are talking about potatoes.