1/2 cup finely ground, quick-cooking Italian
polenta, plus more for baking sheet
2 tsp. quick-rise yeast
1 tsp. salt
1 1/3 cups warm tap water
1 Tbs. extra-virgin olive oil
1 egg, beaten with 1 Tbs. water
In a large bowl, combine the flour, the 1/2 cup polenta, the yeast and salt. Using a wooden spoon, stir to mix well. Add the warm water and olive oil and stir until all of the flour has been absorbed and a dough has formed.
Using your hands, gather the dough into a ball and transfer to a well-floured work surface. Knead the dough until soft and elastic and no longer sticky, about 10 minutes. Work more flour into the dough if needed to reduce stickiness; be sure to keep the work surface well floured. The dough should remain in a rounded shape and not flatten out when left on a work surface for a minute or two. If not, work a little more flour into the dough. Place the dough in a warmed, lightly oiled bowl, turning several times to coat it with oil. Cover with plastic wrap and let rise in a warm place until doubled in bulk, 45 to 75 minutes.
Sprinkle a little polenta on a baking sheet and set aside. Punch down the dough, return it to the lightly floured work surface and knead a few times. Form the dough into a round ball or an oval shape and place on the prepared baking sheet. The dough should retain its shape and not flatten out. Cover loosely with plastic wrap and let rise in a warm place until doubled in bulk, 30 to 40 minutes. While the dough is rising, position a rack in the middle of an oven and preheat to 425°F.
When the dough has risen, using a very sharp, thin-bladed knife or single-edge razor blade, carefully make a slash 1/2 inch deep across the top. Brush the surface with the egg mixture. Bake for 15 minutes. Reduce the oven temperature to 375°F and continue to bake until golden and crusty, 30 to 35 minutes more.
Transfer the loaf to a wire rack and let cool.
Makes 1 round or oval loaf; serves 6 to 8.