Prep the pan and oven: Heat the oven to 350°F (175°C). Grease a 9x5-inch loaf pan and line the long side with a parchment sling. This makes lifting the loaf out a breeze.

Mash the bananas: In a large bowl, mash the bananas with a fork until mostly smooth with a few small lumps. You want about 1 1/3 to 1 1/2 cups of mash.

Whisk in wet ingredients: Add the granulated sugar, brown sugar, oil, eggs, and vanilla. Whisk until the mixture looks cohesive and glossy.

Combine dry ingredients: In a separate bowl, whisk the flour, baking soda, baking powder, salt, and cinnamon. This helps distribute the leaveners evenly.

Bring it together: Add the dry ingredients to the banana mixture. Stir gently with a spatula until the flour disappears. Do not overmix—a few streaks are okay.

Add mix-ins (optional): Fold in nuts or chocolate chips. Keep the folding minimal to protect the crumb.

Fill the pan: Scrape the batter into the prepared loaf pan and smooth the top. If you like, sprinkle a little sugar on top for a delicate crust.

Bake: Place on the center rack and bake for 55–65 minutes. The loaf is done when a skewer inserted in the center comes out with a few moist crumbs but no wet batter.

Cool properly: Let the loaf rest in the pan for 10–15 minutes, then lift it out to a wire rack. Cool at least 45 minutes before slicing to lock in moisture.

Slice and enjoy: Use a serrated knife for clean slices. Serve warm, at room temperature, or lightly toasted with butter.