Mix together the warm coffee and brown sugar in a small pitcher. Mix in the yeast and set aside for a couple minutes to bloom.
In the bowl of an electric mixer, mix together the bread flour, whole-wheat flour and cocoa powder. Add in the coffee/yeast mixture, as well as the honey, butter and molasses. With the dough attachment, mix on medium until a ball begins to form, about 2 minutes. Reduce the speed to low and knead for an additional 6 minutes.
Grease a large bowl with olive oil; put the dough in it and cover with plastic wrap. Place in a warm spot in the kitchen and let rise until doubled in size, about 2 hours.
Divide the dough in half, form into 2 tight balls and put on a baking sheet. Drizzle the tops with olive oil and cover very loosely with plastic wrap. Allow to rise again for 45 minutes to 1 hour.
Preheat the oven to 375 degrees F.
When the dough is ready, remove the plastic wrap. With a serrated knife, cut an X in the top of each round. Carefully transfer the dough to two 10-inch cast-iron skillets. Place both skillets on the center rack of the oven and bake until the crusts are browned and the centers are set, about 30 minutes. Transfer to a cooling rack and allow to cool for at least 15 minutes before slicing.