1. In the bowl of a stand mixer with dough hook attachment, combine boiling water and cereal. Let cool to 100°F, stirring occasionally, about 1 hour.
2. Once cooled, add honey, melted butter, and yeast to cereal mixture. Stir on low speed to combine. Meanwhile, in large bowl, whisk flours to combine.
3. On medium-low speed, add flour mixture, ½ cup at a time, to the bowl just until dough forms, about 1½–2 minutes.
4. Cover bowl with plastic wrap; let dough rest 20 minutes.
5. Uncover and add salt; knead on medium-low speed for 10 minutes, adding just enough of remaining flour mixture until dough pulls away from sides of bowl.
6. Cover bowl with plastic wrap and let dough rise 60–75 minutes, or until dough has doubled in size.
7. Punch down dough. Divide in half.
8. On a lightly floured surface, press one half into a 9-by-6-inch rectangle. Starting at one of the short ends, roll dough into a log, tucking dough under itself as you roll, creating a taut surface along log. Pinch seam to seal. Repeat with other dough half.
9. Lightly spray loaves with cooking spray. Sprinkle oats on clean work surface; roll loaves in oats to coat. Transfer each loaf to prepared loaf pans, seam side down. Cover pans loosely with lightly greased plastic wrap. Let rise 45–60 minutes until nearly doubled.
10. Meanwhile, heat oven to 375°F Bake Mode with a rack set at position “3.”
11. Bake loaves 35–40 minutes until deep golden brown and baked through; an instant-read thermometer inserted in the center the loaf should read 200°F.
12. Cool in pans for 5 minutes. Transfer to wire rack to cool completely before slicing.
13. Store fully cooled loaves tightly in plastic wrap up to three days at room temperature; if freezing, cover with plastic wrap and foil. Freeze up to 2 months.