Preheat oven to 350°F and spray a 9×5 loaf pan with nonstick cooking spray. 

In a medium mixing bowl, mash bananas well. Stir in canola oil, brown sugar, vanilla, egg and stir well. 

On top of the wet ingredients, add the dry ingredients in the order listed, all-purpose flour, whole wheat flour, baking powder, and salt. Gently stir the dry ingredients together and then mix with the wet ingredients just until combined and there are no more streaks of flour in the dough. 

Stir in the chocolate chips. 

Pour batter into prepared loaf pan and bake for 50-55 minutes or until a toothpick inserted into the center comes out clean. 

Let the bread rest for 20 minutes before slicing.