Step 1

Place 2 cups of the hottest water from your tap in the bowl of a stand mixer, add 2 tablespoons cocoa powder, and whisk fully dissolved. Add 1/4 cup instant mashed potato flakes, 2 tablespoons vegetable oil, 2 tablespoons molasses, 1 tablespoon granulated sugar, 2 teaspoons kosher salt, and 1 packet instant yeast. Whisk until combined.

Step 2

Add 2 cups bread flour and 2 cups rye flour. Mx on with the dough hook on the lowest speed until a sticky dough forms, 7 to 10 minutes. Add 2 teaspoons caraway seeds, if using, and mix until fully incorporated, about 2 minutes.

Step 3

Use a rubber spatula or flexible bench scraper to scrape down the sides of the bowl. Cover the bowl with a plate or lid and let the dough rest until puffed and risen, 50 to 90 minutes. The dough might not quite double in size but will be OK as long as it’s puffy. Meanwhile, lightly coat an 8 1/2 x 4 1/2-inch metal loaf pan with cooking spray. (Alternatively, lightly brush with oil or softened butter.) Line the pan with parchment paper, letting the excess hang over the 2 long sides to form a sling.

Step 4

Using oiled hands, punch the dough down in the mixer bowl and roughly shape into a log. Transfer the dough to the prepared pan. Press down firmly to level the dough and push it into the corners of the pan. Lightly oil or coat a sheet of plastic wrap with cooking spray. Place greased-side down loosely over the pan. Let the dough rise until risen about 1 inch above the top of the pan, 50 to 60 minutes. Heat the oven about 20 minutes before the dough is ready.

Step 5

Arrange a rack in the middle of the oven and heat the oven to 350°F. Uncover the bread and bake until deep golden-brown on top (or an instant-read thermometer inserted into the center registers 200ºF), 25 to 45 minutes.

Step 6

Let the bread cool for 10 minutes. Remove the bread from the pan to a wire rack and let cool completely before slicing, about 1 hour.