Preheat the oven to 350°F (175°C). Grease a 9×5-inch loaf pan or line it with parchment paper.
Place the peeled ripe bananas in a large mixing bowl. Mash them with a fork until mostly smooth. A few small lumps are perfectly fine.
Stir the melted coconut oil or butter into the mashed bananas.
Add the honey or maple syrup, beaten eggs, Greek yogurt or sour cream, and alcohol-free vanilla. Whisk until smooth and thoroughly combined.
Sprinkle the baking soda, salt, and cinnamon evenly over the wet mixture and whisk briefly to distribute them.
Add the flour and gently fold it into the wet ingredients with a spatula or wooden spoon.
Stop mixing as soon as the flour is incorporated. The batter for The Best One-Bowl Banana Bread Recipe should be thick and slightly lumpy rather than smooth or runny.
If desired, gently fold in chocolate chips, chopped walnuts or pecans, flax seeds, or chia seeds. Reserve a small amount of chocolate or nuts for the top.
Transfer the batter to the prepared loaf pan and spread the top evenly.
Sprinkle the reserved chocolate chips or nuts over the batter, if using.
Bake for 55–65 minutes. The banana bread is ready when the top is golden and a toothpick inserted near the center comes out clean or with a few moist crumbs rather than wet batter.
If the top becomes too dark before the center is finished, loosely cover the loaf with aluminum foil during the final portion of baking.
Remove the loaf from the oven and allow it to cool in the pan for approximately 10–15 minutes.
Carefully transfer it to a wire rack and allow it to cool further before slicing. Cooling helps the crumb set and produces cleaner slices.