Preheat oven to 350 F (180 C) and spray a 9x5 inch loaf pan with baking spray. Line a piece of overhanging parchment paper across the long side of the pan.
Whisk together oats, wheat flour, all purpose flour, brown sugar, sifted cocoa powder, baking powder, baking soda, salt, ground cinnamon, ginger, and cloves in a medium bowl.
In a separate bowl stir together milk, mashed bananas, maple syrup, eggs, and vegetable oil until evenly mixed.
Transfer banana mixture into the flour mixture and fold together with a rubber spatula until no flour streaks remain. Carefully fold in chocolate chips with a spatula.
Transfer batter into a parchment paper lined loaf pan and allow to sit for 10 minutes.
Sprinkle more oats and chocolate chips across the top.
Place pan on the center of the middle rack in the oven and bake for 65-70 minutes until toothpick comes out clean.
Set pan on wire cooling rack for 15 minutes. Lift up on overhanging parchment paper and remove loaf from pan. Place on cutting board, slice and serve.