Prepare the dough:

1. In a large mixing bowl, whisk together all the dry ingredients including flour, yeast, sugar, and salt.
2. Add water and stir well to combine until no dry flour is visible in the bowl. Make sure to scrape down the sides of the bowl with a spatula. (Lukewarm water and sugar “wakes up” the yeast and speeds up the fermentation, which helps build up gluten strength).
3. Transfer the dough onto a clean and lightly greased surface and knead the dough until the dough ball is smooth, about 6-8 minutes. You can rest the dough covered in the mixing bowl for 5 minutes and continue kneading until smooth.
4. Cover the bowl with plastic cling wrap and let dough rise at room temperature (preferably in a warmer area) for 1 hour until doubled.

Prepare the filling:

1. In a small mixing bowl, add scallions, salt, and oil and stir well to combine. Set aside.

Shape the buns:

1. Use a rolling pin to roll the dough into an approximate 12x9-inch rectangle. Use a silicone brush and brush the scallion filling evenly on top.
2. From the long side of the rectangle, fold the dough in to the 2/3 mark. Take the other long side and fold it in on top, to form a three-layer rectangle approximately 12x3-inches in diameter.
3. Use a pizza cutter or knife to cut the rectangle crosswise into 12 even strips (about 1-inch wide). Make sure all the layers are cut through.
4. Take two strips at a time and stack them up together. Use a chopstick or straw to press down lengthwise in the centre to create an indentation. Hold the two ends and gently stretch it a little.
5. Hang the end side over a chopstick (the side without the indentation), and pinch the two ends together. With the other hand, rotate the chopstick in a full 360 degree circular motion to twist the bun into a coil. 
6. Repeat with the rest of dough strips to form 6 shaped buns

Steam the buns:

1. Prepare to steam the buns by adding some water into a large cooking pot and placing a fitted steamer basket on top. Lightly oil the steamer basket and line it with parchment paper to prevent sticking during steaming.
2. Place the buns into the lined steamer basket and cover with the lid. Set it aside, and let the buns rise for 25 to 30 minutes before cooking. You don't need to wait till the buns double in size, as they will rise further during steaming.
3. Turn the stove on to medium heat and bring the water to a boil. Steam the buns for 15 minutes (covered) over boiling water . Turn off the heat and leave the buns in the steamer for another 5 minutes before uncovering or removing from the steamer. This will help prevent the buns from shrinking due to temperature drop.
4. Serve immediately.