Place the rack in the center of the oven. Preheat the oven to 180ºC (350ºF). Lightly grease a 23 x 13-cm (9 x 5-inch) loaf pan.
In a bowl, combine flour, millet, baking powder, salt and cinnamon. Set aside.
In another bowl, mix the mashed bananas, egg, oil, brown sugar and vanilla extract.
Combine dry and moist ingredients alternately until smooth. Add chocolate. Place the mixture in the bread pan. Bake for 50 minutes to 1 hour or until a toothpick inserted in the centre comes out clean.
