1/2cupunsalted butter at room temperature, plus more to butter pan
1/2cupdark brown sugar
2large ripe bananas, peeled and mashed
1 1/2cupsall-purpose flour, plus more to butter pan
1/2teaspoonkosher or coarse sea salt
1/2cupchocolate chunks or chocolate chips
Pre-heat oven to 350 degrees Fahrenheit, and set a rack in the middle. Butter and flour a 9x5-inch loaf pan, shaking off any excess flour.
In a stand mixer, set with the paddle attachment, beat the butter and sugar on medium speed until completely creamy and smooth, about 3 to 4 minutes. Add the egg and give it a minute to mix in. Add the bananas, cream cheese and vanilla, continue mixing for a minute.
Reduce the speed to low, add the flour, baking soda, baking powder and salt and continue beating for another 3 to 4 minutes, scraping down the sides if need be.
In a small bowl, combine the boiling water with the cocoa powder and stir until well mixed. Add to the mixer and beat for another couple minutes. Lastly, add the chocolate chunks and beat for another minute until fully incorporated.
Scrape into the prepared loaf pan, shake a few times to level the batter. Place into the oven and bake anywhere from 55 minutes to an hour, until a toothpick comes out moist but not wet, the top of bread has browned and is springy to the touch.
Remove from the oven and let cool. Run a butter knife along sides of the pan, turn out onto plate, and then flip onto serving platter, so it is right side up.