Stir ingredients and cover. Allow to ferment at room temperature for 24 hours.

Add water, yeast, both flours, and the poolish to a stand mixer & mix on low with dough hook for 3min to combine.

Increase the speed to high and continue mixing for 4min.

When the dough has fully come together, add caraway seeds, and mix for no more than 30seconds on medium to incorporate. Do not over mix

Remove 60% of dough and put it in a well-oiled bowl, and cover.

Add molasses and cocoa to the dough that is still in the mixer bowl. Mix on low for 30 seconds, then increase the speed to high for another 30 seconds or until well incorporated.

Place into a second well-oiled bowl and cover. Allow both doughs to rise at room temp for 30min.

Stretch dough in the bowl by pulling each side of dough out and folding it into the middle. Perform this for 3 minutes on both doughs. Strength-building fold to both doughs as shown.

Cover again and allow to rise at room temp for 90min.

Prepare 1lb loaf pan with oil or pan spray. Flip doughs onto a floured work surface. Degas each piece into rough rectangles. Place brown dough on top of lighter dough and press to seal together.

Roll into loaf and place in a loaf pan, cover, and proof at room temp for 60-90min.

Score top of the loaf, place preheated 460F oven, spray loaf and oven well with water, and bake for 15 min. Then, reduce heat to 400F and bake for an additional 20min.

Cool on rack, remove from the pan after 5 minutes.