In a large bowl or the bowl of a stand mixer, dissolve the yeast in warm water with a pinch of sugar. Add the sugar, salt, oil, and 4 cups flour, and mix until smooth.
Add remaining flour, ½ cup at a time, to form a soft, smooth dough. Place the dough in an oiled bowl, turn over once to coat the top with oil, and cover with plastic wrap. Let rise for one hour, or until doubled.
When the dough has risen, punch it down gently and divide it in half. Roll the dough up, starting at the short edge, to form a cylinder that is approximately 8 inches wide. Repeat with the remaining dough.
Place the dough, seam side down, into lightly greased bread pans, and cover with plastic wrap. Let rise for one hour, or until the dough is ½ – 1 inch higher than the top of the pan.
Preheat the oven to 375°F. Bake for 30-35 minutes or until the loaves are golden brown. Brush with melted butter, if desired. Remove to a cooling rack and cool before slicing