In a large bowl or a stand mixer, add 370 grams of bread flour, 65 grams of oat flour, 7 grams of instant yeast, 1 1/2 tablespoons of cocoa powder, 1 tablespoon of brown sugar, 1 1/2 teaspoons of salt and an optional teaspoon of espresso powder
Add 1/3 cup of honey and 1 cup of warm water and mix until completely combined
Knead for 5 minutes or until you have an elastic dough (if the dough is very stiff, add an additional tablespoon or 2 of water and knead to incorporate)
Add 3 tablespoons of softened butter and knead for another few minutes or until completely incorporated
Transfer the dough into a lightly oiled bowl, flip a few times and cover with plastic wrap. Rest in a warm place for 60 minutes or until the dough has doubled in volume
Turn the dough out onto a lightly floured surface, gently press out into a rectangle and roll into a cylinder
Transfer the loaf into a greased 8.5”x4.5” loaf pan
In a small dish, whisk a large egg with a tablespoon of honey and a teaspoon of water. Brush the egg wash over the loaf and sprinkle with oats
Cover the loaf with plastic wrap and rest in a warm place for 60 minutes or until puffed to the top of the loaf pan
Preheat your oven to 350°
Bake in a 350° oven for about 45 minutes or until the interior temperature of the loaf reaches 190° (lightly cover the loaf with foil towards the end of the bake if it begins to become too brown)
Transfer the baked loaf onto a cooling rack to cool before slicing with a serrated knife
Store leftover bread in a sealed bread bag or wrapped in plastic at room temperature for 3-4 days