In a small bowl, dissolve yeast in warm water. Let stand until creamy, about 10 minutes.
In a large bowl, combine the yeast mixture with 3 cups flour and the salt. 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 supple, about 10 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 2 hours. Meanwhile, preheat oven to 260 degrees C.
Divide the dough into sixteen equal pieces and form into rounds. Roll rounds into square loaves 5mm thick. Place the on ungreased baking trays. Bake in preheated oven for 4 to 5 minutes, until loaves puff in the middle. Let cool on a wire rack.