Preheat your oven to 350°F (175°C) and grease a muffin tin.
In a mixing bowl, mash the ripe bananas with a fork until smooth.
Stir in the melted butter until well combined.
Add baking soda and salt; mix thoroughly.
Incorporate the sugar, beaten egg, and vanilla extract into the banana mixture.
Gradually mix in the flour until just combined.
Gently fold in the chocolate chips.
Spoon the batter into the prepared muffin tin, filling each cup about 2/3 full.
Bake for 20-25 minutes or until a toothpick inserted comes out clean.
Let the muffins cool in the tin for a few minutes before transferring to a wire rack.