Sourdough Pumpernickel - cooking recipe

Ingredients

sponge
1 cup sourdough starter (133 gm flour, 133 gm water)
1 1/3 cups black coffee (room temperature, 298 gm)
2 cups stone ground rye flour (261 gm)
Dough
2 teaspoons salt (table, 14 gms)
1/4 cup molasses (57 gm)
2 tablespoons cocoa powder
1 cup whole wheat flour (131 gm)
2 cups bread flour (267 gm)
1/2 cup water (scant 1/2 cup, luke warm, 105 gm)

Preparation

Using a proofed 100% hydrated starter, make the sponge in a large bowl.
Cover and let sit on counter for 5 to 12 hours at room temperature. Longer times means a more sour bread.
Add the dough ingredients to the sponge and mix well.
Cover and rest for 20 minutes.
Knead by hand for about 5 minutes adding water or flour to keep the dough tacky, not sticky (not actually coming off on your hands).
Place in a bowl that has been sprayed with oil and cover to let rise. I have a spot that averages 80 F for this and it's ideal.
Stretch and fold every 40 minutes and return to rising, covered.
When 1.5 times it's original volume, (2 to 3 hours depending on temperature) divide and form 2 loaves (freeform or 8 x 4 pans). If freeform, use a rising baskedt or a floured, cloth covered colander.
Rest for 1 hour 30 minutes at 80 F or until it increased in size by 1.5 times.
Preheat oven and a pan on the bottom of the oven for water to generate steam. As loaves are placed in the oven, add 2/3 cup of hot water to the pan.
I invert the loaves onto parchment, score and set on a baking stone, but a sheet pan can be used.
Bake at 375 for about 50 minutes until 205 F internal temperature. I rotate the loaves after 15 minutes and remove the steam pan at that time.
cool on racks.