For the Tangzhong

1. Combine the milk and flour in a small saucepan, and whisk until no lumps remain.
2. Place the saucepan over medium heat and cook the mixture, stirring frequently, until thickened and pastelike; the whisk should leave lines on the bottom of the pan. This will take 1 to 3 minutes, depending on the strength of your burner.
3. Remove from the heat and transfer to the bowl of a mixer.

For the Dough

1. Immediately add the dough ingredients to the mixer bowl in the order listed. The heat from the tangzhong will help warm the cold milk.
2. Using the dough hook, mix on low speed to bring the dough together, then increase the speed to medium-low and continue to mix until the dough is smooth and elastic. This should take about 10 to 12 minutes.
3. Shape the dough into a ball, place it back in the bowl, and cover.
4. Let the dough rise until puffy but not necessarily doubled in bulk—​about 60 to 90 minutes depending on the warmth of your kitchen.

For The Filling

1. While the dough is rising, combine the melted butter with the remaining filling ingredients, stirring until the mixture is the texture of damp sand. Set aside.
2. Lightly grease a baking sheet or line it with parchment.

For the Assembly and Baking

1. Transfer the dough to a lightly floured work surface and press it into a 10 in by 12 in/25 cm by 30.5 cm rectangle about 1/2 in/12 mm thick.
2. Sprinkle the filling over the dough, covering all but a 1/2 in/12 mm strip along one long side.
3. Starting with the filling-​covered long side, roll the dough into a log. Pinch the seam together to seal.
4. Using a serrated knife or dental floss, cut the dough into eight rolls, about 1 1/2 in to 2 in/4 cm to 5 cm each.
5. Place the rolls onto the prepared baking sheet, spacing them at least 2 in/5 cm apart; a 3-​2-​3 arrangement works well. To prevent them from unraveling while they rise and bake, tuck the ends of the spirals underneath the rolls to hold them in place.
6. Cover the rolls with lightly greased plastic wrap and let them rise for 30 to 60 minutes. The rolls should be puffy, and the dough shouldn’t bounce back immediately when gently pressed.
7. Preheat the oven to 375F/190C with a rack in the top third.
8. Uncover the rolls and bake them for 14 to 18 minutes, until they’re a very light golden brown.
9. Remove from the oven and brush the hot rolls with the remaining 1½ Tbsp/21 g of melted butter. Let cool for 10 to 15 minutes before icing.

For the Icing 

1. In a medium bowl, combine the icing ingredients, mixing until smooth.
2. Ice the rolls and serve immediately. If you’re planning to serve the rolls later, wait to ice them until just before serving. Store icing at room temperature, tightly covered, until ready to use.
3. Let the rolls cool completely before wrapping tightly in plastic wrap or placing in an airtight container.