Moist, nutty banana bread made with rich brown butter, ripe bananas, and a hint of cinnamon—tender crumb, bakery-worthy aroma, and easy enough for any day.
Preheat oven to 350°F. Grease a 9 x 5 inch loaf pan and line with a parchment sling.
Brown the butter: Melt butter in a light-colored saucepan over medium heat, stirring until foamy, then nutty and amber with browned bits on the bottom, 5 to 7 minutes. Transfer to a bowl, scraping the browned bits, and cool 10 minutes.
In a large bowl, whisk browned butter with granulated sugar and brown sugar until glossy. Whisk in eggs, vanilla, and sour cream until smooth. Stir in mashed bananas.
In a separate bowl, whisk flour, baking soda, salt, and cinnamon. Add dry ingredients to wet and fold just until no dry streaks remain. Fold in walnuts or chocolate chips if using.
Spread batter into the prepared pan and smooth the top. Tap the pan once on the counter to release air bubbles.
Bake 55 to 65 minutes, until a toothpick inserted in the center comes out with a few moist crumbs. If the top is browning too quickly, tent loosely with foil around 45 minutes.
Cool in the pan for 15 minutes, then lift out to a wire rack to cool completely before slicing.
Store tightly wrapped at room temperature for up to 3 days or freeze slices up to 2 months.
Notes
For best flavor, use very ripe bananas with plenty of brown spots. Let the browned butter cool so it doesn’t scramble the eggs. Avoid overmixing once you add the flour to keep the crumb tender.