01 - Preheat oven to 350°F. Line a 12-cup muffin tray with paper liners or grease lightly.
02 - Whisk together mashed bananas, eggs, melted coconut oil or butter, honey or maple syrup, and vanilla in a large bowl until smooth.
03 - Mix rolled oats, flour, baking soda, baking powder, cinnamon, and salt in a separate bowl.
04 - Add dry ingredients to wet ingredients and stir gently until just combined. Do not overmix.
05 - Fold in walnuts, pecans, or chocolate chips if desired.
06 - Divide batter evenly among muffin cups, filling each about 3/4 full.
07 - Bake for 18 to 22 minutes, until a toothpick inserted into the center comes out clean.
08 - Cool in pan for 5 minutes, then transfer to a wire rack to cool completely.