Method
To prepare the broccoli stems, trim off the hard outer part and slice the more tender inner part.
Thinly slice the fish and combine with the cornstarch, Shaoxing wine and stock powder.
Heat a wok over medium heat and add the oil. Fry the fish for about two minutes until just cooked. Remove with a wire mesh then pour the oil out of the wok. You can save this oil for something else—don't waste it.
Return two tablespoons of oil to the wok then add the ginger. Fry for about 30 seconds then add the broccoli stems. Toss to coat in the oil for a minute then add the onion and garlic and toss for another minute. Add the stock powder, salt and sugar and toss until the broccoli is tender. Return the fish to the wok. If it looks dry, add a little water. Drizzle in just a little of the cornstarch slurry while shaking the wok then transfer to a serving plate.
Garnish with spring onions.