Banana Bread Brownies | Moist, Frosted & Easy Dessert Bars

The first time I made these banana bread brownies, I was trying to use up a few overripe bananas and accidentally created something way better than I expected. Think: the dense chew of a brownie meets the sweet comfort of banana bread, all topped with a rich, nutty frosting. It’s the kind of dessert you make once and never forget—especially if you love bananas.

Why You’ll Love These Banana Bread Brownies

These banana bread brownies are the perfect hybrid treat—moist like banana bread, chewy like a brownie, and sweetly topped with a browned butter frosting that melts in your mouth. They’re an ideal way to use up overripe bananas, and the pecans give a warm, toasty crunch that balances the richness. Whether you’re craving a cozy afternoon snack or a crowd-pleasing dessert bar, this recipe hits the sweet spot every time.

Plus, if you’re a fan of banana-based desserts, you’ll also love these Soft and chewy banana oatmeal cookies for a wholesome dessert option and these Classic banana bread muffins with a moist and tender crumb.

Ingredients You’ll Need

For the Banana Brownie Base:

• 2 eggs – helps bind and add structure
• 1½ cups white sugar – sweetens and caramelizes beautifully
• 1 cup sour cream – adds moisture and slight tang
• 1 stick (½ cup) unsalted butter, room temp – rich and creamy base
• 3 large ripe bananas, mashed – the star flavor
• 2 tsp pure vanilla extract – adds depth
• 2 cups all-purpose flour – gives body and chew
• 1 tsp baking soda – for a little lift
• ¾ tsp kosher salt – balances sweetness
• 2 cups chopped pecans – adds crunch and nutty flavor (optional but recommended)

For the Brown Butter Frosting:

• ½ cup unsalted butter – browned for that nutty, toasted taste
• 3 cups powdered sugar – for sweet, smooth texture
• 1½ tsp pure vanilla extract – layers in flavor
• 3 tbsp whole milk – helps achieve creamy spreadable consistency

How to Make Banana Bread Brownies

Step 1 – Make the Brownie Batter

Preheat your oven to 375°F. Grease and line a 9×13” pan with parchment for easy removal.

In a large bowl, beat the sugar, sour cream, softened butter, and eggs until smooth and fluffy. Add mashed bananas and vanilla extract, mixing until fully combined.

In a separate bowl, whisk together the flour, baking soda, and salt. Slowly add the dry mix into the wet ingredients, stirring until just combined. Fold in chopped pecans if using.

Pour the batter into your prepared pan and smooth it out evenly.

Step 2 – Bake and Cool

Bake for 20–30 minutes, or until the top is golden and a toothpick comes out clean from the center. Cool completely before frosting—it’s worth the wait.

Step 3 – Make the Brown Butter Frosting

In a skillet, melt the butter and cook over medium heat until it foams, turns golden, and smells nutty. Remove from heat and pour into a mixing bowl.

Gradually beat in the powdered sugar. Add vanilla and milk, beating until the frosting is smooth and spreadable. Spread generously over the cooled brownies and slice into bars.

Tips for Best Results

• Use overripe bananas for max sweetness and moisture
• Don’t skip browning the butter—it adds unbeatable flavor
• Let brownies cool completely before adding frosting
• Store them airtight to keep that soft, tender texture

Storage and Freezing Instructions

• Fridge: Store frosted or unfrosted brownies in an airtight container for up to 5 days
• Freezer: Freeze brownies (frosted or not) for up to 2 months. Use parchment between layers and wrap tightly in plastic and foil

Banana Bread Brownies FAQs

Looking for more banana-based treats? Try this Snickerdoodle banana bread that blends cinnamon spice with ripe bananas—it’s another cozy twist you’ll love.

And if you’re the social type, check out more homemade favorites on Kai Recipes’ Pinterest or join the community on Facebook.

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