Preheat oven to 350°F (180°C). Line a 9-inch x 5-inch loaf pan with parchment paper. Oil the pan and paper with coconut oil. Set aside.
Measure your chickpea flour in a medium-size mixing bowl. Using weight: grams or oz for precision. Otherwise, spoon, pack and level your measuring cups. If lumps show in your flour, squeeze between your fingers to remove them. Set bowl aside.
In another large mixing bowl, combine mashed bananas, maple syrup, vanilla extract, cinnamon, apple cider vinegar, and baking powder.
Gradually stir in chickpea flour, make sure your flour has no lumps, or it will form packets of flour in the dough that can taste bitter.
Stir in chocolate chips and transfer the bread batter into the prepared loaf pan.
Bake for 55 to 65 minutes, tent the loaf pan with foil paper after 40 minutes to prevent the top from browning too fast. You know it's ready when a skewer inserted in the center of the loaf comes out clean with no to a little crumb on it.
Store the bread in a sealed cake box in the fridge for up to 4 days or freeze slices and thaw the day before serving.