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 mixing bowl, mash the bananas until smooth. Add eggs, Greek yogurt, honey, oil, and vanilla extract. Whisk thoroughly until fully incorporated and uniform in texture.
03 - In a separate medium bowl, sift together whole wheat flour, baking soda, baking powder, cinnamon, and salt. Whisk to ensure even distribution of leavening agents and spices.
04 - Gradually pour the dry ingredients into the wet mixture. Fold gently using a spatula just until flour disappears—stop immediately when combined to prevent dense muffins. Small lumps are acceptable.
05 - Sprinkle chopped walnuts or pecans over the batter along with dark chocolate chips if using. Fold in briefly to distribute evenly without overworking the mixture.
06 - Divide the batter equally among the 12 prepared muffin cups. Fill each cup approximately 3/4 full to allow room for rising during baking.
07 - Bake at 350°F for 18–22 minutes until domes form and tops are golden brown. Test doneness by inserting a toothpick into the center—it should emerge clean or with a few moist crumbs.
08 - Let muffins rest in the tin for 5 minutes to set. Carefully transfer to a wire cooling rack and allow to cool completely before storing or serving.