Heat water and milk and allow to become lukewarm. Add in dry yeast and mix until yeast dissolves.
In a large mixing bowl mix dry ingredients: flour, salt and sugar.
Melt butter and allow to cool to room temperature. Then add melted butter and 1/2 beaten egg into the yeast mixture.
Using a spatula, add the yeast mixture into the flour mix. Mix until just combined.
Place dough onto a clean floured surface and knead with hands for 10 minutes. The dough will become round, smooth, and elastic.
Put the dough in a greased big size bowl, cover with plastic wrap and let it rise in at room temperature (about 1 1/2 - 2 hours).
If you are making this during cold weather, you can heat your oven at the lowest temperature for about 3-5 minutes, then turn off your oven. Leave the door open and allow and place the dough into the oven to prove.
Divide the dough into 12 pieces and flatten the dough into thin discs. Stuff char siu mixture into each disc, folding and pinching it like a large xiaolong bao/soup dumpling. Make sure your buns are completely sealed. Place buns fold-side down onto a lined baking sheet.
Cover buns with plastic wrap and allow the buns to rest and rise again for 1 hr-1.5 hrs. Do the fingerpoke test to make sure that your dough is coming back halfway. At that point, your buns are ready to bake.
Preheat oven to 350 degrees F.
Brush the tops of your buns with a beaten egg. Bake for 13-18 minutes or until golden brown.
While baos are baking, make glaze for the buns by mixing in sugar, water, and honey and boiling on high until thickened to coat the back of a spoon.
Take buns out of the oven and allow to cool until lukewarm. Then brush on the glaze onto the buns. Serve warm.