Blanch the broccoli florets in boiling salted water for about 10 minutes.
Heat the oil in a wok. Add the garlic, ginger and celery. Fry briefly till soft. Add the sliced spring onion whites and keep stir-frying on medium-high heat for about 2 minute(s).
Add the mushrooms and saute on high-medium heat for about 2 minute(s) or till they are very lightly fried and glossy. Add rest of the ingredients except the spring onion greens and keep tossing on high heat for about 3 minutes or till the vegetables are crunchy-cooked. Mix in the spring onion greens and put off the flame.
Serve Hot