Mix 6 cups of flour, water, and apple cider vinegar in a stand mixer or large mixing bowl until completely combined. You are desiring a stiff dough that pulls away from the sides.
Cover with plastic wrap or a towel and a plate and let stand overnight for about 12 hours.
After 12 hours of soaking, add salt, yeast, and sugar to the dough. Using a dough hook, knead dough for five minutes, adding ½ cup more flour if needed about halfway through. You are desiring a sticky yet manageable dough.
Transfer dough to a greased bowl, cover, and let rise one hour.
After first rise, scrape half of the dough onto a lightly floured surface. I use unbleached all purpose flour.
To shape the loaf, gently press out into a rectangle shape. Then roll up the dough and tuck under the ends.
Repeat with second loaf.
Place shaped loaves into greased bread loaf pans, cover, and let rise for another hour or until doubled in size.
After second rise, place the two loaves into a preheated 350 degree oven for 30-40 minutes. You want a golden brown color and it to sound hollow when you tap on the top. The internal temperature should also read about 190 degrees F.
Use a knife to go around the edge of the loaves to loosen them from the pans. Then turn the bread out onto a cooling rack and let cool for an hour before slicing.