Spray four 8 1/2 x 4 1/2 inch bread pans with non-stick spray; set aside.
Mix water, oil, honey, yeast, gluten, potato flakes and white flour in a Bosch mixer. Add salt and 4-5 cups of whole wheat flour, beat till smooth. Let sit for 20 minutes.
Add enough whole wheat flour to make a soft dough, then knead for five minutes in the Bosch.
On a counter sprayed with non-stick spray, shape the bread dough into four loaves. Place dough seam side down in prepared loaf pans.
Let the bread rise in a warm place till doubled, (30-60 minutes) then bake at 350 degrees for about 30 minutes or until lightly browned.
Let the bread cool in the pan for about 5 minutes, then turn out onto a wire rack to cool completely.
Brush the tops of hot bread with melted butter if desired.