Combine water, sugar and yeast in a small bowl; let stand until foamy, about 5 minutes.

In the bowl of an electric mixer fitted with dough hook attachment (or by hand in a large bowl), combine the water mixture, butter, 1 egg, 2 cups flour and salt on medium-low speed until a smooth batter forms, about 1-2 minutes.

Gradually add remaining 1 1/4 cups flour, 1/2 cup at a time, until a soft, smooth ball of dough is formed. The dough should feel elastic and slightly tacky to the touch. Increase speed to medium-high and beat for 3 minutes.

Lightly oil a large bowl or coat with nonstick spray; place dough in bowl, turning to coat. Cover with a clean dishtowel and let stand in a warm spot until dough has doubled in size, about 45 minutes to 1 hour.

Gently deflate dough by punching down. Working on a lightly floured surface, divide into 8 equal pieces, weighing the pieces as needed; shape each piece into a smooth ball.

Line a baking sheet with parchment paper. Place rolls onto the prepared baking sheet; flatten each ball to 3 inches. Cover with a clean dishtowel and let stand in a warm spot until dough has doubled in size, about 45 minutes to 1 hour.

Preheat oven to 375 degrees F.

In a small bowl, whisk together remaining egg and milk. Brush tops of dough with egg mixture; sprinkle with sesame seeds.

Place into oven and bake until golden brown, about 15-18 minutes.