Add the Butter (1/3 cup) into the Milk (1 cup), and stir together for a while. Sprinkle over the Instant Dry Yeast (1 package) into the mixture, and combine well. Let it sit for 5 minutes.
Separate Egg (3) Yolks and set aside.
Add the All-Purpose Flour (4 cup), Salt (1 teaspoon), Granulated Sugar (1/3 cup), Egg Yolks, and yeast mixture into a standing mixer. Combine everything well.
Take your dough, form it into a ball shape and place it into a greased bowl. Cover it with a plastic wrap, and place it in a warm place for about 2 hours.
Form the dough into an elongated bread shape, and cut it into 12 equal pieces. Form each piece into a ball shape, and place it into a baking dish. Cover the buns with a towel, and place them in a warm place for about an hour.
Preheat oven to 375 degrees F (190 degrees C).
Bake in preheated oven for about 25 minutes.
Brush the buns with Butter (3 tablespoon) and serve!