In a small saucepan, combine the water, milk, and flour.

Heat over low-medium heat, mixing frequently with a rubber spatula for about 5 minutes or until it thickens.

Remove from heat and set aside to cool.

In a glass measuring cup, combine the warm milk, sugar, and yeast. Allow to sit 2-3 minutes until foamy to ensure the yeast activates properly.

Once foamy, whisk in the egg until well combined.

In the bowl of a stand mixer fitted with a hook attachment, combine the flours, milk powder, salt, tangzhong starter, and milk mixture.

Mix on medium speed until a ball forms around the hook, then add the softened butter.

Mix on medium-high speed for about 8 minutes until smooth and passes the windowpane test.

Transfer the dough to a greased bowl, cover, and place in the fridge to proof overnight. Alternatively, the dough can proof for about 1 hour in a warm environment.

Once proofed, divide the dough into 12 parts, about 40g each.

After they have been divided, shape the rolls. Flatten each dough piece into a disk, then fold the edges over into its center, forming a smooth surfaced ball. On a non-floured surface, roll the ball (seam side down) with a cupped hand until smooth. Set aside to rest and repeat with the remaining rolls.

Once all of the rolls have been shaped, quickly roll them again with a cupped hand, then place in a 12"x8" oval dish or 9" square pan spaced about 1" apart.

Cover the rolls and allow to proof for about 1 hour in a warm environment until doubled in size.

Meanwhile, preheat the oven to 350 degrees F.

Brush the proofed rolls with an egg wash and bake for about 20 minutes until golden and internal temp is 190 degrees F.

While the rolls are baking, make the honey butter.

In a small saucepan, combine the butter and honey, and place over low-medium heat.

Stir frequently until fully melted, then pour into a bowl.

Once the rolls come out of the oven, immediately brush each of them liberally with the honey butter.

Sprinkle some flaky sea salt on each, and enjoy!