What does "crossing the bridge rice noodles" mean?

Rice flour is a special name of Yunnan food.

Rice flour is made of rice. Their cross section is long and round. They are white and hard. After cooking in boiling water, take it out and put it in the broth. Generally, chopped green onion, soy sauce, salt, monosodium glutamate, spicy oil sauce, meat sauce and other seasonings are mixed and eaten while it is hot.