Chinese broccoli, also known as gai lan, is a leafy green vegetable that is commonly stir-fried and served with oyster sauce. The dish is sweet, salty, and savory, with a slightly bitter taste from the broccoli. The oyster sauce is made from soy sauce and oyster extract, which give it a rich flavor and a thick, viscous texture. It is often served as a side dish or as part of a larger meal in Chinese cuisine.