Place warm water in the bowl of a stand mixer fitted with a dough hook OR a large bowl. Dissolve yeast in water and let stand 5 minutes until foamy.
Mix honey, egg, and coconut oil into yeast mixture until smooth. Add salt, oats, whole wheat flour, and 4 cups all purpose flour to bowl and mix on low speed OR with a wooden spoon if making dough by hand until dough pulls away from sides of bowl, about 2 minutes of mixing. (if dough seems a bit wet, add additional all-purpose flour by the tablespoon until dough pulls away from sides of bowl)
If making dough in stand mixer, knead dough in mixer on low speed 5-7 minutes until dough is stretchy and elastic. If making dough by hand, turn dough onto a lightly floured surface and knead by hand until dough is stretchy and elastic, about 10 minutes of kneading.
Place dough in a greased bowl, turning once to grease top. Cover bowl with plastic wrap and let rise in a warm place at room temperature 1 to 1-1/2 hours until dough is doubled in size.
Once dough has doubled in size, preheat oven to 350F. Line two 9x5 loaf pans with parchment paper OR lightly grease. Set aside.
Punch risen dough down and turn onto a floured surface. Divide dough in half and roll each half out into a 9x12 inch rectangle. Tightly roll each rectangle starting at the short side, pinching ends to seal. Transfer each loaf to prepared pans, tucking ends under.
Brush each loaf with egg white/water mixture and sprinkle with additional oats. Allow loaves to rise in a warm place at room temperature 30-45 minutes until doubled in size.
Bake loaves at 350F 25-30 minutes until bread is a deep golden brown and registers 190F on a kitchen thermometer.
Cool bread completely in pans on a wire cooling rack. Once cooled, remove from pans and use a serrated knife to cut into slices. Enjoy!