Put water in a large bowl. Add brwon sugar and active dry yeast. Let yeast develop for about 5 minutes. Add molasses, rye flour, vital wheat gluten, and cocoa. Beat well, then let sit for ten minutes. Mix in melted butter and salt. Mix in 1 cup of bread flour. Knead in enough of the remaining bread flour to make a soft dough and knead for 8-10 minutes. Put dough in an oiled bowl. Cover with a damp cloth, and allow to rise for one hour or until doubled. Divide the dough into two pieces. Gently knead to work out air bubbles and form into loaves and place in two greased loaf pans. Cover with a damp cloth and allow to rise another hour or until the dough is nearly doubled. Bake in a 400 degree preheated over for 25 to 28 minutes. Immediately remove from pans and cool on a wire rack. Brush melted butter over top of loaves if desired. Enjoy