Scald milk in a saucepan over medium-low heat. Mix Red River and oatmeal flakes together in a very large bowl. Stir together and allow it to cool until lukewarm (to have crunchy bread, do not heat the milk).
Meanwhile, in a two cup measuring cup, add two packets of yeast to 1 1/2 cups warm water. Stir and allow yeast to bloom (foam) for approximately 10 minutes.
Add walnuts and salt. Stir in 3 cups whole-wheat flour. Add all-purpose flour, one cup at a time until the dough forms a manageable ball. Move dough to a lightly floured counter top. Knead, adding all-purpose dough until the dough no longer “absorbs” or needs flour and is not sticky to touch. Try not to add too much flour, it makes a drier bread. I used about 4 1/3 cups all-purpose flour.
Knead for 10-15 minutes until dough makes a nice smooth, soft ball. Cut into four and shape each piece into a round artisan loaf, tucking sides under to stretch the top of the loaf into a round shape. Place on parchment paper on two baking sheet in a warm location and allow to rise until double in size. Space them so they have room to rise without touching.
Preheat oven to 375° F.
Bake for approximately 20 minutes. Reduce the heat to 350°F and continue to bake for about 20-25 minutes.
Recipe by Just a Smidgen at https://justasmidgen.com/2011/08/18/crunchy-low-fat-health-bread/