If you want to get a feel for the life of a longtime Beijing resident, you could start by walking the city streets until your boogers turn black. Or you could eat some traditional Beijing snacks, foods that have been satisfying the city's populace for centuries.
If you visit early in the morning you'll find yourself surrounded by the city's elderly population drinking their mung bean milk and eating their pea flour cake, and picking their¡­ you know.
 

Mung Bean Milk (Dou Zhi/ 豆汁)
Probably the most famous Beijing snack (běi jīng xiǎo chī北京小吃), mung bean milk is actually the fluid remnants of the mung bean noodle making process. It looks grayish-green, tastes mostly sour with a tinge of sweetness, and has a peculiar odor. it's definitely an acquired taste. First-timers often drink mung bean milk accompanied with a few Chinese-style pickle wedges, which locals say makes it easier to go down.
Mung Bean Milk, which was first drunk about one thousand years ago, is the Number one snack when people are talking about Beijing Snacks. It is actually remnant of mung bean when it is used to make starch. When served, it must go with pickles, which are thinly cut and sprayed with cayenne pepper oil.
It will taste better, especially for those who try it for the first time. Most people will find it hard to swallow because of its flavor, but if you could manage to try for the second time, maybe you will like it. Some people have got into the habit of drinking it and they even would search everywhere and wait a long time in lines for it. Mung Bean Milk is also rich in protein, vitamin C and dietary fiber and has some effects like appetizing, relieving summer heat, detoxifying and some other effects that account for its popularity among many people.
Beijing Noodles with Soybean Sauce (Zha Jiang Mian/ 炸酱面)
Beijing Noodles with Soybean Sauce (zhá jiàng miàn 炸酱面) is a treat not to be missed. Although customarily made from diced pork fried in a thick brown bean sauce, most restaurants now just use ground pork. The noodles should be hand rolled. Delicious and filling for a snack or a meal, this dish is a favorite in Beijing homes.
It consists of wheat noodles topped with a thick sauce made of chunjang (a salty black soybean paste), diced meat and vegetables, and sometimes also seafood.
It is originated from a Chinese dish, but the version familiar to Koreans is usually only found in Chinese restaurants in Korea or those serving Korean customers. This dish is also available in other countries where there is a large Korean population.
In China (or at least in the Beijing region), authentic Zha Jiang Mian can be found, prepared with a different sauce and ground pork rather than seafood. The name of this Chinese dish is zhajiangmian.Although spelled differently, the pronunciation of the name of the Chinese dish is nearly identical to that of its Korean counterpart. Despite the similar ingredients, due to its thick sauce, jajangmyeon looks darker and has a different taste than the original, zhajiangmian.