Preheat oven to 425 degrees Fahrenheit.
To a liquid measuring cup, mash the brown bananas until you have about 1 1/2 cups of mashed banana. It's okay if you have a few little chunks of banana. Set aside.
To a medium-sized bowl, whip the softened butter with a hand mixer until creamy.
Add the brown sugar and mix again until light and fluffy. Add the eggs and mix again until completely incorporated.
Drizzle in the vegetable oil while mixing and add the yogurt and vanilla extract. Add the mashed banana and mix together.
Put the hand mixer away and pull out a wooden or large spoon. Add the flour to the bowl. Add the salt and baking soda right on top of the flour and carefully mix (not letting any of the baking soda or salt leave the bowl as you mix). Mix just until the flour is just incorporated and only a few dry streaks remain.
Add mini chocolate chips, chopped nuts or dried fruit and lightly mix.
Lightly grease or line with parchment paper a 9 by 5 pan, affiliate link (see recipe note for muffin instructions). Pour the mixture into the pan and smooth the top with a spatula.
Bake for 10 minutes at 425 degrees. After ten minutes, lower the temperature to 350 degrees and bake for another 45-55 minutes until baked all the way through. Stick a sharp knife or toothpick into the center of the banana bread. If it comes out clean (with no batter sticking to it), it is ready to pull out of the oven.