In a large bowl, whisk together the water and sourdough starter until the starter is evenly dispersed.

Add the oil, molasses, and honey and then stir until everything is combined.

Add the all-purpose flour, whole wheat flour, cocoa powder, and salt.

Mix until a dough forms: Stand Mixer Method: Mix with the dough hook on low speed for 4 to 6 minutes until a smooth dough forms. By Hand: Mix until no dry flour remains, then knead the dough for 2 to 3 minutes until it begins to feel smooth.

Cover the bowl and let the dough rest for 30 minutes.

Perform one set of stretch and folds. Lift one side of the dough and then stretch it upward, and fold it over itself. Turn the bowl 90 degrees and repeat the action on all four sides.

Cover the bowl and let the dough rest for 30 minutes.

Repeat this two more times, resting the dough for 30 minutes between each set, for a total of 3 sets of stretch and folds.

After the final stretch and fold, leave the dough covered to continue fermenting. Bulk fermentation is complete when the dough has increased by about 50-75%, and feels noticeably lighter, with small bubbles throughout the surface. I like to aim for a final dough temperature of 75-78°F (24-26°C). In a 72-75°F kitchen, this typically takes 3.5 to 5.5 hours after the stretch-and-fold period is complete.

Lightly flour your work surface and turn out the dough and gently press it into a rectangle roughly about 9X11 inches.

Starting with the short side, roll the dough tightly into a log, creating surface tension as you roll.

Pinch the seam closed and place the dough seam-side down into a lightly greased loaf pan.

Cover the pan and let the dough rise until the highest point is about 1 inch above the rim of the pan. The dough should look puffy and spring back slowly but not fully when you gently press it. This usually takes 1 to 2 hours.

Preheat the oven to 350°F (177°C).

Brush the surface lightly with water. Sprinkle with oats and gently press them into the dough so the oats stick to the dough.

Using a bread lame or razor blade, score the loaf down the center

Place a second loaf pan upside down directly over the loaf pan. This traps steam during the first stage of baking, and helps create better oven spring and a softer crust.

Bake the bread with the top pan in place for 25 minutes and then carefully remove the upper pan and continue baking for 20 to 25 minutes more. The loaf is done when it is deep brown and registers 200-205°F (93-96°C) in the center. You can check the temperature using a meat thermometer.

Remove the bread from the pan immediately and place it on a wire rack. Allow the loaf to cool completely, at least 2 hours, before slicing and devouring it.