Dan Dan means carrying pole in Chinese. The pole was made of bamboo or wood. A single person balances the yoke over one shoulder, with one large basket being suspended from each end. It was widely used in Sichuan before people could afford modern transportation. The anecdote says that Dan Dan Noodle was invented by a hawker in mid nineteenth century in Sichuan. Of his two baskets, one carried the stove and pot, another the noodle and ingredients. People were impressed by its mobility with the carrying pole. They started calling it Dan Dan Noodle.
After 150 years, there are some fixed rules about Dan Dan Noodle. First, it has to be in the small bowl about the size of your fist. If in anything bigger than that, you should know it is not authentic. The reason is simple: the bowls were used to be carried around in a basket on a carry pole. They have to be small. Second, there can’t be soup in it. For the same reason: no space. Third, there has to be chili oil and minced pork or beef. Chili oil is for the spicy flavor, while the minced meat was loved by the manual laborers when protein was expensive to get in old days. The rest are up to the chef. But you have to follow the three golden rule, otherwise it is not Dan Dan Noodle.