Make the Tangzhong

1. Whisk the milk and bread flour together in a small saucepan over low heat.
2. Cook for 2–3 minutes, whisking constantly, until the mixture thickens into a smooth, translucent paste.
3. Transfer the paste to a small bowl. Cover with cling film (pressed directly against the surface to prevent a skin from forming) and let it cool completely to room temperature.

Mix and Knead the Dough

1. Warm the 125 ml of milk in a heatproof jug (about 30 seconds in the microwave) until lukewarm (approx. 38°C / 100°F).
2. Stir in the caster sugar and active dry yeast. Cover with a clean tea towel and leave to stand for 5 minutes until frothy.
3. In the bowl of a stand mixer, whisk together the bread flour and fine sea salt. Make a well in the centre.
4. Pour the egg, the frothy yeast mixture, and the cooled Tangzhong paste into the well.
5. Attach the dough hook and mix on low speed until a shaggy dough forms.
6. With the mixer still running, gradually add the softened butter, one piece at a time, letting each piece incorporate before adding the next.
7. Increase the mixer to medium speed and knead for 8–10 minutes. The dough is ready when it is smooth, elastic, and passes the windowpane test (you can stretch a small piece into a thin, translucent membrane without it tearing).
8. Lightly oil the sides of your mixing bowl.
9. Roll the dough around right inside the mixing bowl until its surface is completely covered with oil.
10. Cover the bowl tightly with a lid or cling film and place it in a warm spot to proof for about 1 – 2 hours, or until doubled in size.

Shape the Dough

1. Once the dough has doubled, remove the lid or cling film, dust lightly with flour, and knock out the air. Transfer to your work surface.
2. Knead gently for 2 minutes and shape into a smooth ball by dragging the dough toward you while tucking the edges underneath. Cover with a tea towel and rest for 15 minutes.
3. Divide the dough into 3 equal pieces (total weight is 703 g, so about 234 g each).
4. Shape each piece into a smooth ball by pulling the sides down and rolling lightly on the work surface. Cover with a tea towel and rest for 15 minutes.
5. Flip each dough ball sticky-side up, then flatten it by pressing with your knuckles into a flat disc.
6. Roll the disc into a rectangle roughly 15 x 26 cm. Fold both long sides inward so the width of the dough fits into your bread tin.
7. Roll it tightly from the top down and pinch the end to seal. Arrange the rolled dough balls side-by-side in the bread tin. Repeat this step for the remaining dough pieces.
8. Cover the bread tin with a tea towel and let the dough proof for the second time (about 45–60 minutes, or until it rises near the rim).

Bake the Bread Loaf

1. When the second proof is almost complete, preheat the oven to 180℃ (fan).
2. For a golden finish, mix the egg and milk to create the egg wash, and brush a thin layer over the top of the loaf.
3. Bake in the preheated oven for 23–25 minutes, or until deep golden brown.
4. Once done, remove the loaf from the tin and allow it to cool on a wire rack. Serve warm and enjoy!