Heat the oven to 350F. Coat a 9X5 loaf pan with cooking spray and line with a parchment paper.
In a bowl, mix flour, baking powder, baking soda and salt. Set aside.
In a large bowl, mix melted butter and sugar until light and sugar is dissolved.
Add in the eggs one at a time and mix well.
Mash the bananas and add them to the eggs. Mix well until fully incorporated.
Add in buttermilk and cinnamon. Mix well.
Add the flour mixture to the eggs and banana mixture. Mix using a spatula until no flour lumps is visible.
Fold in the chocolate chips.
Pour the batter into the loaf pan and smooth the top with the back of a spatula.
Bake in the oven for 45 minutes to an hour, until a toothpick inserted in the middle of the bread comes out clean.
Let the bread cool down for 30 minutes before slicing.