Combine 2-½ cups flour, undissolved yeast, sugar, salt and baking soda in a large mixer bowl.
Heat milk and water until very warm (120° to 130°F). Add to flour mixture.
Beat 2 minutes at medium speed of electric mixer, scraping bowl occasionally.
Stir in remaining flour to make a stiff batter.
Spread batter in 2 (8-½ x 4-½-inch) loaf pans that have been greased and sprinkled with cornmeal.
Cover; let rise in warm, draft-free place until doubled in size, about 45 minutes.
Bake in preheated 400°F oven for 25 minutes or until done.
Remove from pans; cool on wire rack.
Slice; toast to serve.