In large mixing bowl combine whole-wheat flour, 1-1/2 cups of the all-purpose flour, baking soda, and salt, mixing well to combine. Make a well in the center of flour mixture; pour in milk. Using a large metal spoon, mix well to combine.
Using your hands, knead in bowl until well combined.
Sprinkle remaining all-purpose flour onto work surface; turn dough out onto floured surface and knead until smooth, 1 or 2 minutes.
Shape dough into 7-inch round loaf about 3 inches thick and transfer to nonstick baking sheet. Using a sharp knife, cut a cross about 1 inch deep through the surface of the dough.
Bake for 40 - 45 minutes (until a toothpick inserted in center comes out dry). Transfer bread to wire rack and let cool completely.