In a stand mixer, combine all the ingredients except the tsp of oil and knead with the dough hook. Keep kneading until the dough is soft and pliable and smooth, but not sticky. Add a bit more flour or water if dough seems too wet or dry. Once the dough is ready, grease the bowl with a tsp of oil, cover with plastic wrap and allow to rise for 1 hour. While the dough is rising, make the sauce, slaw, and get the chicken coating ready to go.
Set up your steamer over a pot of water with about 2 inches of water in the pot. Make sure you have 24 4x4 parchment squares ready and some oil spray or oil and a brush as you will need them when you shape the bao.
Punch the dough down and knead it a little to get it smooth. Cut the dough into 12 equal pieces and shape into a ball. Allow to rest 5 minutes to let the dough relax a bit, then roll into a 4x7 oval. Brush one square of parchment lightly with oil and place half the oval on it. Grease another square and fold the oval in half with the greased square in the middle (like filling). This will allow you to open the bun enough later to fill it with filling. As you finish each bun, place it in the steamer, not touching the others.
Once all are done, close the steamer and allow the buns to rise for another 20 minutes. While you are waiting, start cooking the chicken.
Turn on the heat under the pot and set it to high. Once the steam starts coming out, reduce to medium and steam for 10 minutes. Turn off the heat but do not open the steamer for at least 5 more minutes. This allows the buns to set so they don't deflate when you open the top.