Combine 2 cups whole-wheat flour, 1 cup bread flour, yeast and salt in large bowl.
Heat water, honey in saucepan until very warm (125 to 130 degrees F).
Gradually beat water mixture into flour mixture at low speed. Stir in remaining whole-wheat flour and 1 cup bread flour with wooden spoon, 1/2 cup at a time, to make soft dough. Stir in raisins and walnuts.
Knead dough on floured surface until smooth and elastic, about 10 minutes, working in 1/2 cup bread flour as needed to prevent sticking. Shape into ball. Cover with plastic wrap; let rest 10 minutes.
Divide the dough into four equal pieces. Roll each piece on floured surface into 14-inch-long cylinder. Place 2 tablespoons cornmeal on waxed paper; roll the cylinders in the cornmeal.
Sprinkle each of 2 large baking sheets with 1 tablespoon cornmeal. Place 2 baguettes on each sheet. Cover; let rise in warm place until doubled in bulk, about 30 minutes.
Heat oven to 425 degrees F. Place remaining 3 tablespoons bread flour in a small sieve; sprinkle evenly over loaves. Cut four 1/2-inch slashes into the top of each loaf.
Bake in 425 degree F oven 20 minutes or until loaves sound hollow when tapped. Remove to wire rack to cool. Makes 4 baguettes (12 slices each).