In a large mixing bowl, dissolve yeast in warm water. Let it sit for about 5 minutes until frothy.
Add sugar, butter, salt, egg, and 2 cups of flour. Beat until smooth. Stir in remaining flour to form a soft dough.
Turn onto a floured surface; knead until smooth and elastic, about 6-8 minutes. Place in a greased bowl, turning once to grease the top. Cover and let rise in a warm place until doubled, about 1 hour.
Punch dough down. Turn onto a lightly floured surface; divide into 12 pieces. Shape each into a ball. Place in a greased 13x9-in. baking pan. Cover and let rise until doubled, about 30 minutes.
Bake at 375°F for 15-20 minutes or until golden brown. Remove from pan to wire rack to cool.