Baked Red Bean Bun (烤豆沙包)

Ingredients:

Dough:

• 3 1/4 cup (480 g) Bread Flour
• 3/4 cup (120 g) All-Purpose Flour
• 1/3 cup + 1 Tsp (90 g) Sugar
• 1/2 Tsp (10 g) Salt
• 2 Tsp + 2 tsp (20 g) Dry Milk
• 1 1/3 cup (300 ml) Warm Water
• 3 tsp Active Dry Yeast
• 1 Large Egg
• 60 g Sweet Buttercream

Fillings:

• 3 cup  - Red Bean Paste (Recipe found here)
• 1/2 cup Softened Unsalted Butter + 1/3 cup Brown Sugar
• 1/2 cup All-Purpose-Flour

Others:

• 1 Egg + 1 Tsp Water  - for Egg Wash
• 2 Tsp Black Sesame Seeds - for Sprinkles

Preparation:

1. Set aside an egg and the butter at the room temperature
2. In a mixing bowl, add bread flour, all-purpose flour, sugar, salt, dry milk and stir them altogether
3. Beat the egg in a small bowl.  Pour it into dry ingredients.
4. In a small bowl, add water and microwave it for about 45 seconds. Add active dry yeast and let it sit for a couple of minutes to bloom the yeast.  Once bubbles formed, stir it well.   Add it into the mixing bowl and mix everything together
5. Melt the butter in the microwave.  Pour it into the mixing bowl.  Combine everything well.
6.  Cover the mixing bowl with a lid or a plastic wrap.  Let the dough sit for about 30 minutes.
7. Knead the dough for about 3 minutes until the smooth surface is formed.  During the kneading process, rub the hand with flour if needed as the dough might be a bit sticky.
8.  Transfer the dough back to the mixing bowl, cover it with the lid/plastic wrap and let it sit until its size is doubled.  Depending on the room temperature, the duration might vary but it usually takes about 2 hours.
9.  Lightly flour the kneading surface or a cutting board.  Take the dough out of the mixing bowl and make it a smooth round shape.  Cut it into 16 pieces. Weigh each piece with the scale and each of the piece should weigh about 72g.  At the end, you'll end up with 15 pieces of small dough.
10.  Make each piece a round shape.  Lightly flour its bottom and let it rest on the cutting board or a flat surface.  Repeat this for all 15 pieces.  Cover them up with the plastic wrap and rest them for about 30 minutes.
11.  Meanwhile, prepare the fillings as follows:

• In a small bowl, mix well the unsalted butter with the brown sugar.  Set aside.
• In another small bowl, pour the flour and set aside.
• Divide red bean paste into 15 different pieces and make each of them a ball.
• For each red bean paste ball, make a hole in the middle and fill it in with the butter and brown sugar mixture.  Seal the ball.  Dip it into the flour and lightly coat the ball.  Repeat this for the remaining 14 pieces.

12. After 30 minutes, take each dough piece, make a hole in the middle and fill it with the red bean paste ball.  Seal it and make it a round shape.  Lightly coat its bottom with the flour.  Repeat this for the remaining pieces.  Cover them back with the plastic wrap and let them sit until its size is doubled.  Again, the duration varies depending on the room temperature.  For the room temperature of 70F degree, it usually takes about 1.5 to 2 hours.
13. Preheat the oven to 375F degree.
     
Putting Everything Together:
1. Line 2 trays of cookie baking sheet with the parchment paper.  Transfer dough pieces on there.
2. In a small bowl, prepare the egg wash by beating the egg and water together. Brush the top and side of each bun thoroughly with the egg.  Sprinkle the top with black sesame seeds.
3.  Bake them at 375F degree for 12-14 minutes.
     I bake both of the trays together- one at the middle rack and one at the bottom rack. After 14 minutes, take out the tray on the middle rack as it was done.  Move the other tray to the middle rack from the bottom rack.  And bake additional 5 minutes until they are done.
4. Cool them on the cooling rack.
5. Serve warm or put them in the zip-loc bag and serve the next day.