Preheat oven to 350℉. Prepare two muffin pans by filling them with cupcake liners, then set aside. Mash the bananas with a fork in a small bowl and set aside.
In a large mixing bowl, sift the flour, baking powder, baking soda, and salt. Set aside.
In the other mixing bowl, whisk together the extra-virgin olive oil, brown sugar, and granulated sugar. Add the eggs one at a time as you whisk. Add the vanilla extract, yogurt, sourdough discard, and mashed bananas.
Gradually add the dry ingredients to the bowl of wet ingredients, mixing with a wooden spoon or rubber spatula until just combined, making sure to scrape the sides of the bowl to incorporate all the ingredients. Finally, fold in the chocolate chips.
Use a 1/4 measuring cup to pour the muffin batter into the muffin cups. This recipe makes 12-18 muffins. Top with a few chocolate chips if you desire. Bake muffins for 20 minutes. You'll know the muffins are done when you stick a toothpick in the center and there is no wet batter stuck to the toothpick. Moist crumbs are fine. Enjoy!