Preheat the oven and prepare the pan

• Preheat the oven to 220 °C.
• Grease a 9x5-inch loaf pan and line it with parchment paper.

Mash the bananas

• In a large bowl, mash the bananas until smooth, leaving a few chunks.

Mix the wet ingredients

• Add the melted butter, granulated sugar, brown sugar and eggs to the bananas and mix until smooth.
• Add the sour cream and vanilla extract and mix until well combined.

Whisk the dry ingredients

• In a separate bowl, whisk the flour, baking soda and salt.

Combine the batter

• Fold the dry ingredients into the wet just until combined, without overmixing.
• Gently fold in the chocolate chips.

Fill the pan

• Pour the batter into the prepared pan.
• Optionally sprinkle extra chocolate chips on top.

Bake

• Bake at 220 °C for 10 minutes.
• Reduce the temperature to 175 °C and continue baking for 50-60 minutes, until a toothpick inserted in the center comes out with a few moist crumbs.
• Lightly tent with foil partway through to prevent over-browning.

Cool

• Cool in the pan for 15 minutes, then transfer to a rack to cool completely.