Spray a 9-inch by 5-inch loaf pan with nonstick spray.
Place an oven rack in the middle of the oven. Preheat oven to 350 degrees.
Mash bananas with a fork.
In a large mixing bowl add: granulated sugar, brown sugar and melted butter . Mix to combine.
Add in the egg, sour cream, vanilla, and mashed bananas.
Mix until well combined and smooth.
Add in the flour, baking soda, and salt and mix until just combined.
Fold in the mini chocolate chips with a spatula until evenly distributed.
Pour the batter into the prepared loaf pan and smooth. Top with 2 tablespoons mini chocolate chips.
Place in the oven and bake for 30 minutes. After 30 minutes cover the top of the bread with foil to protect from over browning.
Check bread after 55 minutes-1 hour by inserting a toothpick. Remove from oven when toothpick comes out clean.
Allow bread to cool in the pan on a cooling rack from 10 minutes before removing it. Cool fully on rack before slicing.