Prep your pan and oven: Heat the oven to 350°F (175°C). Grease and line a 9x5-inch loaf pan with parchment, or line a 12-cup muffin tin, or grease an 8-inch square pan.
Mash the bananas: In a large bowl, mash bananas until mostly smooth with a few small lumps for texture.
Whisk in wet ingredients: Add eggs, oil, yogurt, brown sugar, and vanilla.
Whisk until well combined and glossy.
Combine dry ingredients: In a separate bowl, whisk flour, baking soda, baking powder, salt, and cinnamon. This prevents clumps and ensures even rise.
Fold gently: Add dry ingredients to the wet mixture. Stir with a spatula just until no dry streaks remain. Do not overmix.
Add mix-ins (optional): Fold in nuts or chocolate chips.
Reserve a few for the top if you like a bakery-style look.
Fill and smooth: Pour into the prepared loaf pan (or scoop into muffin cups about 3/4 full, or spread into the cake pan). Sprinkle reserved mix-ins on top.
Bake: Loaf: 55–65 minutes, until a tester comes out clean or with a few moist crumbs.
Muffins: 18–22 minutes.
Snack cake: 28–34 minutes.
Cool properly: Let cool in the pan for 10–15 minutes. Then lift out to a rack to cool fully.
This sets the crumb and keeps it tender.
Slice and enjoy: Use a sharp serrated knife for the loaf to avoid tearing the delicate crumb.