Place flour, brown sugar, warm water, salt, olive oil, and yeast into the pan of the bread machine in the order recommended by the manufacturer. Select dough cycle; press Start.

Place a pizza stone in the oven. Preheat the oven to 375 degrees F (190 degrees C). The oven must be preheated for at least 30 minutes before baking.

Deflate dough and turn it out onto a lightly floured surface. Form dough into 2 loaves. Place loaves seam-side down on a cutting board generously sprinkled with cornmeal. Cover loaves with a damp cloth and let rise until doubled in volume, about 40 minutes.

Beat together egg and 1 tablespoon water in a small bowl until well combined. Brush risen loaves with egg mixture. Make a single long, quick cut down the center of loaves with a sharp knife. Gently shake the cutting board to make sure loaves are not sticking. If they stick, use a spatula or pastry knife to loosen. Slide loaves onto the hot pizza stone with one quick but careful motion.

Bake in the preheated oven until loaves sound hollow when tapped on the bottom, 30 to 35 minutes.