Guess what food this is

It is a common staple food and a traditional delicacy in Lanzhou, which is known and loved by every Lanzhou person. Its history can be traced back to the JiaQing period, and it was formed through continuous innovation and improvement. It can be said to be beautiful in color, flavor, and taste, and is well-known all over the country. It has also been identified by the state as one of the three major Chinese-style fast food pilot varieties.
People can eat three meals a day, but very few people will eat it at night, it depends on everyone's living habits. Lanzhou people tend to eat it in the morning, and those from outside the city may also eat it at night. Therefore, such restaurants in Lanzhou are often only open from 6:00 am to 4:00 pm because they need to ensure the freshness of the ingredients.
It takes at least four hours to make this dish every time, and the preparation starts around 3 o’clock in the morning, and finally ensures that people who go to work or school in the morning can eat it hot at around seven. We have a saying about this kind of food, "one clear, two white, three green, four red, five yellow", which refer to the different ingredients used to make this food. If something is made that doesn't fit that statement, it's not made successful. At the same time, there are many kinds of it, you can choose according to your favorite.
After I settled in Beijing, I found that the price of this kind of food is different in Beijing and Lanzhou. In Lanzhou, you only need to spend 6 yuan to get a full serving, but in Beijing it can be as expensive as 30 yuan. Maybe you will say that the labor cost of the two places are different, but the fact is that there are restaurants making this kind of food everywhere in our place.
There are its signs all over our country, but they are not authentic, because the original flavor can only be achieved in Lanzhou.