Dissolve yeast in warm water. Add buttermilk, 2 tablespoons butter and the next 7 ingredients. Stir in 2 cups flour. Beat until smooth. Stir in enough remaining flour to form a soft dough, which will be sticky.
Turn onto a heavily floured surface; knead until smooth and elastic, 6-8 minutes. Place in a greased bowl, turning once to grease top. Cover and let rise in a warm place until doubled, about 75 minutes.
Punch dough down. Turn onto a lightly floured surface; divide into 4 portions. Divide each portion into 6 pieces; shape each piece into a ball. Place in a greased 13x9-in. baking pan. Cover and let rise until doubled, about 50 minutes.
Preheat oven to 375°. Bake rolls until golden brown, 25-30 minutes. Cool 5 minutes before removing from pan to a wire rack. Brush with remaining butter.