01 - Preheat the oven to 350°F and line a 12-cup muffin tin with paper liners or grease lightly with cooking spray.
02 - In a large bowl, mash the bananas until completely smooth. Whisk in eggs, Greek yogurt, honey, oil, and vanilla extract until fully incorporated and creamy.
03 - In a separate medium bowl, whisk together the whole wheat flour, baking soda, baking powder, cinnamon, and salt until evenly distributed.
04 - Gradually add the dry ingredients to the banana mixture, folding gently with a spatula until just combined. Be careful not to overmix—the batter should remain slightly lumpy.
05 - Gently fold in the chopped nuts and optional dark chocolate chips until evenly distributed throughout the batter.
06 - Divide the batter evenly among the prepared muffin cups, filling each approximately three-quarters full.
07 - Bake for 18-22 minutes, or until a toothpick inserted into the center of a muffin comes out clean and the tops are golden brown.
08 - Allow the muffins to cool in the pan for 5 minutes, then transfer to a wire rack to cool completely before serving.