Method
1 Toss fish, oyster mushrooms, olive oil and coriander together in a large bowl.

2 Cook fish and oyster mushrooms on a heated, oiled grill pan or barbecue hotplate, until tender. Transfer fish and mushrooms to a plate and cover to keep warm.

3 Bring a large saucepan of water to the boil. Add the thick ends of the choy sum and boil for 1 minute. Add remaining vegetables and cook for 30 seconds. Drain well.

4 To make oyster sauce, combine ingredients in a saucepan. Bring to the boil and then remove from heat.

5 Serve fish on vegetables and drizzle with oyster sauce.