Cut the king oyster mushrooms into bite-sized pieces.
Slice the onion and Cheongyang chili pepper.
Heat cooking oil in a pan and sauté the mushrooms.
Add onions and Cheongyang chili pepper, and stir-fry together.
Add soy sauce, oligosaccharide syrup, and minced garlic, then simmer.
Transfer the finished braised mushrooms to a serving dish.