Mix sugar, corn oil, salt, water and 1 cup (236ml) of sourdough starter together in a large bowl. Sift the flour and add to the mixture. Grease or oil the dough. Place the dough in an oiled bowl, cover, and let rise overnight.
The next day, knead the dough for 10 minutes. Divide in half, and place into two greased 4 x 8 inch bread pans. Allow the dough to double in size.
Bake at 350 degrees F (175 degrees C) for 40 to 45 minutes, or until bread is golden brown and taps hollow. Turn out to cool on wire racks.