We are familiar with this 炸酱面 Zhajiangmian, a noodles dish commonly found in Chinese cuisine.
But in Beijing, some places they served this noodle dish in its unique way. The ingredients are separated from the noodles, so you have to mixed it yourself.
The sauce is combination of yellow soybean and the sweet bean. Adding with variety of crunchy vegetables to complete a bowl of Beijing style of Zhajiangmian here.