In the bowl of a stand mixer, stir together the milk and yeast. Add 1½ cups of flour (180g) followed by the butter, sugar, egg, and salt.
Beat with the paddle attachment at medium-low speed for about 1 minute until combined. Scrape down the bowl and beater and switch to the dough hook.
Add another 1¾ cups of flour (210g) and mix on medium until the dough begins to pull away from the sides of the bowl, about 2 minutes. If the dough is still very wet and sticking to the sides of the bowl, add the additional ¼ cup of flour a tablespoon at a time.
Continue mixing for 2 more minutes at medium speed, until the dough balls up around the dough hook and pulls away from the side of the bowl (the bottom may still stick to the bowl). The dough should look smooth and bounce back quickly when pressed.
Place the dough in an oiled bowl, cover with plastic wrap, and place in a warm place (about 75°F) to rise until doubled in size, 45 minutes to 1 hour.
Once risen, grease a 9x13-inch baking dish with softened butter or spray with nonstick spray.
Punch down the dough and turn it onto a lightly floured surface. Divide into 15 equal pieces (about 55g each). Keep the floured side of the dough on the countertop and cover the pieces loosely with a piece of plastic wrap or a kitchen towel.
Working with one piece at a time, pinch the corners of each piece together at the center (keeping the floured side of the dough on the outside), then flip over to place the pinched side on a clean, not floured surface.
Cup your hand over the ball and move in a tight circular motion to shape each ball. This will pull the edge in, creating a tight ball and smooth roll.
Arrange the dough balls in the prepared pan evenly spaced apart, cover with plastic wrap and allow to rise until visibly puffed or almost doubled in size, 30 to 45 minutes.
After 15 minutes of rising, preheat the oven to 350°F.
Bake for 20 minutes or until very puffed and the tops are a deep golden brown. Brush the hot rolls with melted butter. You can serve them immediately or let them cool before serving.
