In a small saucepan, combine 1/4 cup of water and 1/4 cup of flour. Stir over medium heat until it thickens.

In a large mixing bowl, whisk together the bread flour, all-purpose flour, sugar, salt, and yeast.

In another bowl, mix the milk, softened butter, and the prepared tangzhong.

Pour the wet ingredients into the dry ingredients and mix until a dough forms.

Knead the dough for about 10 minutes until it becomes smooth and elastic.

Place the dough in a greased bowl and cover it with plastic wrap or a kitchen towel. Let it rise in a warm place for about 1 hour or until doubled in size.

After the first rise, punch down the dough to release the air.

Divide it into three equal pieces and shape each piece into a smooth ball.

Place the shaped dough balls into a greased loaf pan, cover, and let rise for another 30 minutes.

Preheat your oven to 350°F (175°C). Bake the bread for 30 minutes or until golden brown.