Place flour, brown sugar, warm water, salt, olive oil and yeast in the pan of the bread machine in the order recommended by the manufacturer. Select dough cycle; press Start. Place pizza stone in oven and preheat to 375 degrees F (190 degrees C). Oven must be preheated at least 30 minutes before baking. Deflate the dough and turn it out onto a lightly floured surface. Form dough into two loaves. Place the loaves seam side down on a cutting board generously sprinkled with cornmeal. Cover the loaves with a damp cloth and let rise until doubled in volume, about 40 minutes. In a small bowl, beat together egg and 1 tablespoon water. Brush the risen loaves with egg mixture. Make a single long, quick cut down the center of the loaves with a sharp knife. Gently shake the cutting board to make sure that the loaves are not sticking. If they stick, use a spatula or pastry knife to loosen. Slide the loaves onto the pizza stone with one quick but careful motion. Bake in preheated oven for 30 to 35 minutes, or until loaves sound hollow when tapped on the bottom.