In a stand mixer, combine the flour, sugar, instant yeast, butter, and salt. Mix well until the ingredients come together.

Add the milk and mix on medium speed for about 12 minutes. When you stretch a bit of the dough, it should stretch without tearing and look slightly translucent.

Place the dough in a round bowl, cover with plastic wrap, and let it rise for about 40 minutes or until nearly doubled in size. The warmer the room, the faster the dough will rise.

Divide the dough into 6 or 7 portions and shape each into a ball. Place them on a baking sheet and cover with plastic wrap. Brush the tops with the reserved egg white and sprinkle with sesame seeds if desired. Cover again with plastic wrap. Let rise for 1 to 2 hours or until doubled in size, depending on room temperature.

Preheat the oven to 400°F (204°C).
Spray the inside of the oven with a little water or place a pan of boiling water on the bottom rack to create steam.
Bake the rolls for about 20 minutes, until golden brown.
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