Prepare all ingredients.

Make three wells in the bread flour and add sugar, yeast, and salt separately.

Mix the ingredients with a spatula.

Add 1 egg and milk or water, then knead the dough until no dry flour is visible.

Add butter and knead for 10 minutes until smooth.

Shape the dough into a ball, cover with plastic wrap, and let it rise in a warm place for 40 minutes or until doubled in size.

Divide the dough into 50-55g portions.

Divide the red bean paste into 35g portions and shape into balls.

Roll each dough portion flat with a rolling pin.

Place a ball of red bean paste in the center of each dough piece.

Wrap the dough around the filling and shape into a ball.

Press the top slightly, cover with plastic wrap, and let rise for another 30 minutes in a warm place.

Brush the tops with beaten egg.