Combine the dough ingredients in the bowl of a stand mixer fitted with the dough hook.
Mix on low (speed 2 on a KitchenAid) until combined and watch that the dough becomes smooth and slightly sticky--it should adhere to the bottom of the bowl while kneading. If it's too sticky, you can add flour 1 Tablespoon at a time, waiting until it's incorporated before adding any more. If the dough is too dry, you can add warm water 1 Tablespoon at a time.
Knead for 5 minutes, then transfer to a clean bowl.
Cover and keep in a warm, draft-free place to allow the dough to rise til doubled in size, about 2 hours. (I turn my oven on the lowest temperature for a few minutes, turn it off, leave the light on and put the bowl there.)
During the last hour of the dough rising, combine the bacon, water, honey, soy sauce, rice vinegar, sesame oil, sriracha, and red pepper flakes in a medium sauce pan.
Cook over medium heat until it starts to boil.
Remove 3 Tablespoons of the fluid, add to it the cornstarch, and whisk til combined.
Pour back into the bacon mixture, stir, and continue cooking until thickened. Set aside to cool.
Cut out 12 parchment squares for the next stage...
Line 2 baking sheets with parchment paper and set aside.
Once the dough has risen, turn it out onto a lightly floured work surface. Divide into 12 equal pieces.
Flatten 1 piece of dough into a disc, put 2-3 teaspoons bacon filling in the center, and gather the edges up in the middle, pinching to seal, so you have a little packet of meat.
Place on a prepared baking sheet and pop in the warm oven to wait until ready to steam.
Repeat with the rest of the dough and filling.
Fill a large sauce pan with 2-3 inches of water, place in it the steamer basket, and place 4 parchment squares in the basket. Put buns on top of the parchment squares, cover, and cook on medium-high temperature, steaming for 10 minutes.
Check that the exterior of the buns has hardened a bit and isn't sticky. Cook for a couple more minutes, if necessary, then transfer to wire racks.
Repeat with remaining buns.
Eat warm; if cooled, re-steam or microwave for 30 seconds before consuming.