Mix all of the ingredients for the stir fry sauce in a small bowl. Set aside.
Pour a splash of sesame oil into a wok and then stir fry the oyster mushrooms until golden.
Next, sprinkle in the chilli flakes and the crushed garlic. Continue to stir fry for a minute.
Pop in the broccoli and then add the stir fry sauce, that was mixed up earlier. Make sure it's all well coated, then serve with sesame seeds on top.