Oyster sauce chicken with bok choy is one of the most popular Chinese dishes. Shiitake mushrooms are added to this recipe which is good and safe to eat. Shiitake mushrooms are high in magnesium, vitamin B6 and vitamin D. They are low in calories and fat. Scallions and green onions are actually the same thing! Scallions are low in calories and are high in vitamin C, vitamin A, potassium, magnesium, vitamin B6, iron, and calcium.