In a large bowl, dissolve yeast and sugar in warm water.
Stir in butter, salt and two cups of the flour.
Stir in the remaining flour, 1/2 cup at a time, beating well after each addition. When the dough has pulled together, turn it out onto a lightly floured surface and knead until smooth and elastic, about
8 minutes.
Lightly oil a large bowl, place the dough in the bowl and turn to coat with oil. Cover with a damp cloth and let rise in a warm place until doubled in volume, about 1 hour.
Deflate the dough and turn it out onto a lightly floured surface. Divide the dough into two equal pieces and form into loaves. Place the loaves into two lightly greased 9x5 inch loaf pans. Cover the loaves with a damp cloth and let rise until doubled in volume,
about 40 minutes.
Preheat oven to 375°F.
Bake for about 30 minutes or until the top is golden brown and the bottom of the loaf sounds hollow when tapped.
Five minutes before done, brush melted butter on the crust and return the loaves to the oven.