Wash the mushrooms thoroughly and cut them into bite-sized pieces.
Thinly slice the onion and garlic.
Heat cooking oil in a pan and sauté the garlic.
Once fragrant, add the onion and mushrooms and stir-fry.
Add soy sauce, oligosaccharide syrup, and water, then simmer over medium heat until the mushrooms are cooked.
Sprinkle with pepper to finish.