Preheat oven to 350 degrees F.
Line a 9×5 loaf pan with parchment paper, making sure the parchment is hanging over the sides of the loaf pan. Spray with nonstick spray.
In a large bowl, cream butter and sugar together for about 2 minutes until smooth.
Whisk in the egg.
Add the mashed bananas and vanilla extract. Mix until well combined.
Add the flours, baking soda, baking powder, and salt. Mix until just combined.
Fold in the chocolate chips.
Pour the mixture into the loaf pan and top with more chocolate chips.
Bake for 55-65 minutes until a toothpick inserted in the center of the loaf comes out clean.