Begin by heating your oven to 350°F (175°C). This ensures a steady bake and helps your bread rise perfectly. While it’s warming up, take out your trusty 9-by-5-inch loaf pan and give it a good coating of nonstick cooking spray to keep the bread from sticking.

In a medium bowl, combine the flour, Dutch-process cocoa powder, baking soda, sea salt, and the cinnamon (if you’re using it). Whisk these together until evenly blended. This step is essential as it helps distribute the baking soda and cocoa throughout the batter.

Now, let’s tackle those bananas. In a large mixing bowl, take your overripe bananas and mash them thoroughly using a fork. You're aiming for a smooth consistency that resembles a thick puree; those lumps will bake out later.

Next, pour in the melted butter and your choice of oil to the mashed bananas. Stir them together until completely combined. Then, add in the brown sugar, egg, and pure vanilla extract. Mix it all until you have a smooth and glossy mixture.

Gradually add the dry ingredients to the banana mixture. Be careful not to mix vigorously—your goal is just to incorporate the ingredients until they are barely mixed. Overmixing can lead to dense bread, and we definitely don't want that!

Gently fold in 3/4 cup of the chocolate chips. They’ll melt just slightly during baking, creating delicious pockets of chocolate goodness throughout the bread.

Pour your batter into the prepared loaf pan, making sure it’s evenly distributed. Sprinkle the remaining 1/4 cup of chocolate chips on top for a decadent finish.

Slide the pan into the oven and bake for about 50 to 65 minutes. As you reach the 50-minute mark, check with a toothpick. It should come out mostly clean; a few melted chocolate smudges are totally fine! If it’s still gooey, give it a few more minutes.

Once baked, remove the pan from the oven and place it on a wire cooling rack for about 15 minutes. This allows the bread to cool slightly and makes it easier to remove from the pan.

Run a knife around the edges of the pan and carefully extract the loaf. Let it cool on the rack until warm, then slice it up. The enticing smell will have everyone gathering around!