Preheat the oven to 350°F. Coat the muffin tin with cooking spray or butter (optional: use muffin paper liner).
Smash the ripe bananas using a fork or potato masher. Add brown sugar, eggs, vanilla extract, oil and mix.
In a bowl: add flour, salt, baking powder & baking soda while mixing everything together. (I highly recommend sifting the dry ingredients before adding to the wet ingredients, this will make the batter fluffy and not lumpy).
Combine wet and dry ingredients together. Mix until well combined. Add ¾ cup of chocolate chips and fold with spatula.
Use an ice cream scooper or spoon to measure even portions. As you carefully place each scoop of batter in the muffin tin (should be exactly 12 scoops). Sprinkle ¼ cup of chocolate chips on top of the batter.
Bake for 18-20 minutes or until lightly golden brown. Let the muffins cool in the tin for about 5 minutes and then transfer them to a baking rack to finish cooling completely.