Banana Bread Brownies

This is a brilliant hybrid dessert. You get the moist, dense, comforting flavor of banana bread, combined with the rich, fudgy texture of a brownie, often topped with a creamy frosting. It’s the best of both worlds.

There are two main ways to interpret “Banana Bread Brownies”:

The Fudgy Bar: A dense, moist banana bread baked in a brownie pan, sometimes with chocolate chips.
The Frosted Version: A spiced banana bread base topped with a tangy brown butter or cream cheese frosting to mimic a frosted brownie.

Here is the ultimate guide, featuring a recipe for the latter (which is often the showstopper), plus a variation for a simpler, fudgy chocolate chip version.

Banana Bread Brownies with Brown Butter Frosting

This recipe yields a perfectly spiced, incredibly moist banana “brownie” base topped with an unforgettable brown butter frosting that tastes like liquid gold.

Yields: 16 bars (9×13 inch pan)
Prep time: 20 minutes
Bake time: 20-25 minutes

Ingredients

For the Banana Brownie Base:

1 ½ cups mashed ripe bananas (about 3-4 large bananas)
1 cup granulated sugar
½ cup brown sugar, packed
1 cup unsalted butter, melted and slightly cooled
2 large eggs
1 tsp vanilla extract
2 cups all-purpose flour
1 tsp baking soda
½ tsp salt
1 tsp cinnamon
Optional: ½ cup chopped walnuts or chocolate chips

For the Brown Butter Frosting:

½ cup (1 stick) unsalted butter
2 cups powdered sugar
1 tsp vanilla extract
2-3 tbsp milk (or heavy cream)
A pinch of salt

Instructions

Part 1: Make the Banana Brownie Base

Preheat & Prep: Preheat your oven to 375°F (190°C) . Grease a 9×13 inch baking pan or line it with parchment paper for easy removal.
Combine Wet Ingredients: In a large bowl, mix the mashed bananas, granulated sugar, and brown sugar until combined. Whisk in the melted butter, then the eggs and vanilla extract. Mix until smooth.
Combine Dry Ingredients: In a separate bowl, whisk together the flour, baking soda, salt, and cinnamon.
Combine Wet and Dry: Gradually add the dry ingredients to the wet ingredients, stirring just until combined. Be careful not to overmix; a few streaks of flour are fine. If using, fold in the walnuts or chocolate chips.
Bake: Pour the batter into the prepared pan and spread it evenly. Bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs. The top should be golden brown.
Cool Completely: Place the pan on a wire rack and let the brownies cool completely. This is crucial—if the brownies are even slightly warm, the frosting will melt and slide right off.

Part 2: Make the Brown Butter Frosting

Brown the Butter: In a light-colored saucepan (so you can see the color change), melt the butter over medium heat. Stir constantly. It will begin to foam and sizzle. After a few minutes, the foam will subside and you’ll see small golden brown specks forming at the bottom of the pan. The butter will smell nutty and fragrant. Once it reaches this stage, immediately remove it from the heat to prevent burning. Pour it into a heatproof bowl to stop the cooking process. Let it cool for about 10-15 minutes; it should still be liquid but not piping hot.
Make the Frosting: Add the powdered sugar, vanilla extract, salt, and 2 tablespoons of milk to the browned butter. Beat with an electric mixer until smooth. If the frosting is too thick, add the remaining tablespoon of milk until it reaches a spreadable consistency. If it’s too thin, add a little more powdered sugar.

Part 3: Assemble and Serve

Frost the Brownies: Once the brownies are completely cool, pour the brown butter frosting over the top and spread it into an even layer.
Set (Optional): For cleaner slices, you can let the frosting set for about 30 minutes. If you’re impatient (like me), you can dig in immediately for a gooey, melty experience.
Slice and Serve: Slice into 16 squares. For extra fanciness, drizzle with a little melted chocolate or sprinkle with flaky sea salt.

Alternative: Fudgy Chocolate Chip Banana Bread Brownies

If you want a one-layer bar that’s more like a traditional brownie (dense and fudgy) with banana flavor, try this variation. It’s essentially a banana bread with a higher fat-to-flour ratio.

Ingredients for Fudgy Version:

½ cup unsalted butter, melted
1 cup granulated sugar
1 large egg
1 tsp vanilla extract
1 ½ cups mashed ripe bananas (about 3-4)
1 cup all-purpose flour
¼ tsp salt
½ tsp baking soda
1 cup semi-sweet chocolate chips

Instructions:

Preheat oven to 350°F (175°C). Grease an 8×8 inch pan.
Whisk melted butter and sugar together. Add egg and vanilla, then mashed bananas.
Fold in flour, salt, and baking soda until just combined. Do not overmix.
Fold in chocolate chips.
Bake for 30-35 minutes. The center should be just set. These are meant to be fudgy, so a toothpick might come out with moist crumbs, not completely clean.
Cool completely in the pan before slicing.

Tips for Banana Bread Brownie Success

Use Very Ripe Bananas: The riper the banana, the sweeter and more intense the flavor. Spotty, almost black bananas are ideal. They also mash more easily and provide more moisture.
Don’t Overmix: Overmixing the batter develops gluten, which will make your brownies tough and bread-like, rather than tender and brownie-like. Mix until the flour just disappears.
Cool Before Frosting: Patience is key. Warm brownies will turn your beautiful frosting into a puddle.
Brown Butter is Worth It: If you’ve never browned butter before, it might seem fussy, but it takes only 5 extra minutes and adds an incredible nutty, caramelized depth that takes these brownies from good to unforgettable.