For the dough: In a large bowl, combine the whole wheat and unbleached flours, yeast and 1/2 teaspoon salt. Mix well. In a cup, stir the water and olive oil, then pour into the flour mixture. Stir with a wooden spoon, until the dough becomes stiff and the flour is all incorporated. In the bowl or on a lightly floured counter, knead the dough for about five minutes, until smooth and elastic. Let the dough rest for a few minutes, covered with a clean towel.