Make the tangzhong by combining 2 tablespoons (20 grams) bread flour, 2 tablespoons (27 grams) water, and 4 tablespoons (60 grams) whole milk in a small saucepan. Cook over medium heat, whisking constantly, until thickened, 30 seconds to 2 minutes. Let cool to room temperature.

In a small bowl, combine 1 tablespoon (9 grams) active dry yeast and ½ cup (120 grams) milk at 90-95°F (32-35°C). Let sit for 10 minutes.

In a stand mixer with the dough hook attachment, combine 2 ½ cups (320 grams) bread flour, ¾ teaspoon (3 grams) fine sea salt, and ¼ cup (56 grams) granulated white sugar. Add the tangzhong and yeast-milk mixture, and 1 egg at room temperature. Mix on low speed, scraping the sides as needed, until the dough comes together. Increase speed to medium-low and gradually add 3 tablespoons (42 grams) softened unsalted butter, one tablespoon at a time, mixing until fully incorporated. Mix for 5-7 minutes until smooth and elastic.

Shape the dough into a tight ball and place in a lightly greased bowl. Cover with a damp towel and let rise for 1-2 hours at room temperature until doubled in size.

Punch down the dough and divide into 9 equal pieces, about 75 grams each. Roll each piece into a tight ball and place in a greased 9x9-inch baking pan. Cover with a damp towel and let rise for 1-2 hours until puffed and nearly doubled.

Preheat oven to 350°F (175°C). Brush the rolls with an egg wash (1 egg beaten with 2 tablespoons milk).

Bake for 28-30 minutes until golden brown.

In a small saucepan, combine 1-2 finely chopped garlic cloves and ¼ cup (56 grams) unsalted butter. Heat over medium, sweat the garlic for 30 seconds, then remove from heat.

Immediately brush the hot rolls generously with the garlic butter and sprinkle with flaky salt.