Add the ingredients listed under "tangzhong". Whisk to make lum free and cook to make rough stirring continuously. This could take 2-3 minutes. Set aside to cool.
Add the tangzhong and all the ingredients listed under 'dough' into the bread machine and set it in dough cycle. Let it rise for an hour.
In the meantime, mix the cream cheese, powdered sugar, and cocoa powder to a silky smooth texture. Set in refrigerator.
Once the dough is ready, knead, punch, roll, and divide into nine portions.
Roll each dough smooth and then roll flat into 5-in diameter circle. Scoop about a tablespoon of the filling. gather the ends of the dough together from one direction, sealing it to shape into a ball. Roll and place it on a lined baking sheet.
Repeat with rest of the dough. Cover and set aside for 30 minutes. In the meantime, preheat the oven to 375 degrees.
Brush the top with qauafaba and bake for 16-17 minutes.
While the bun is baking, mix the ingredients for the drizzle. Transfer to apiping bag and snip at the end to pipe.
Once the bun has cooled completely, drizzle the espresso glaze on top of the buns.
Serve with coffee/milk, or as such.