Prepare two 8 1/2 x 4 1/2-inch loaf pans by greasing them with butter and covered with cornmeal; set aside.
In the bowl of an electric mixer fitted with a paddle attachment, mix the flour, yeast, sugar, salt, and baking soda together.
In a small saucepan over low to medium heat, warm up milk and water to very warm, between 120-120 degrees.
Add to flour mixture and combine well.
Change paddle attachment to dough hook and gradually add remaining 3 cups of flour to this.
Divide dough in half and place each into the prepared loaf pans. Cover with a towel and place in a warm spot to rise for 1 1/2 hours.
Preheat oven to 400 degrees, and place pans in oven for 25 minutes.
Immediately remove loaves from pan and place on wire rack to cool.