Put water, brown sugar and yeast in the bowl of a stand mixer. Stir well, then let stand for about 5 minutes.
Add molasses, rye flour, vital wheat gluten, cocoa and caraway seeds. Beat well, then let sit for ten minutes. Mix in melted butter and salt.
Mix in 1 cup of the bread flour and stir until well blended, then stir in enough extra bread flour to make a soft dough. Attach dough hook and let the machine knead the dough for 8 to 10 minutes. Transfer to an oiled bowl and let rise for 1 hour.
Punch down dough and divide it into two pieces or leave as 1. Shape into two balls or make 1 big ball. Set them side by side (or by itself if making 1) on a parchment lined pan. Cover (I use two overturned mixing bowls) and let rise for another hour.
Preheat oven to 450 degrees F.
Bake the loaves for about 20 minutes, being careful not to let the top get too brown. If you are making 1 loaf, it will take about 25 minutes. To test of the bread is done, stick a meat thermometer in the bread and make sure it registers at least 205 F. Let cool completely.