Combine ingredients for lemon dressing in a bowl. Set aside
Scaling the fish (If not done already):
Most of the time the internal parts have been removed, but some are not, especially if you buy them from Asian market. You can have them removed for you. You may need to do the "scaling" on your own. Use a knife and scrap the scales off the meat by going on the opposite direction of the scales. It may be messy, as the scales may "fly" all over the places. I recommend getting a clean trash bag big enough for you to do the scaling inside the bag, so the scales will not go anywhere else and you don't have to worry that they will go down your kitchen sink.
Cut slits at an angle on the fish where the flesh is thick, about 3 slits are sufficient. Place the fish on the steaming dish
Steaming the fish:
Bring water in the steamer to a boil. Steam fish over high heat for 11 minutes or until cooked through, the flesh will easily flake if it's cooked. Remove and pour away the steaming liquid. You can see the eyes of the fish will turn opaque in color and the mouth will open up once it is cooked
Drizzle the dressing over the fish and steam again for about 30 seconds. Remove
Scatter the coriander leaves on top as garnish. Serve immediately