Banana Bread Bars with Brown Butter Frosting offer the comfort of classic banana bread in a fuss-free, crowd-pleasing form. They balance nutty, caramel notes from brown butter with the mellow sweetness of ripe bananas. Each bite combines a tender crumb with silky frosting—a treat anyone can master, whether you’re a baking novice or a seasoned home baker.
The Allure of Banana Bread Bars
Why settle for plain banana bread when you can enjoy bars? These bars are soft, slightly dense, and sturdy enough for portable snacking or serving at gatherings. They fit in lunch boxes, picnic baskets, and dessert trays. You get all the familiar banana flavor, but with an extra richness from the brown butter.
What Sets These Bars Apart:
– Luscious, deeply flavored frosting from browned butter.
– Moist banana crumb from overripe bananas and sour cream.
– Simple process, easily doubled for a crowd.
Let’s dive into what you’ll need and how to create these irresistible bars.
Ingredient Breakdown
The Bars
- Granulated sugar: Sweetens and helps keep the crumb soft.
- Sour cream: Adds tang and retains moisture, ensuring the bars stay tender.
- Unsalted butter: Provides richness; use unsalted for full control over savory-sweet balance.
- Large eggs: Bind the ingredients for stability while adding lightness.
- Mashed very ripe bananas: At least three medium bananas (the browner the peel, the better the flavor).
- Pure vanilla extract: Lifts the warm flavors and rounds out the banana and butter notes.
- All-purpose flour: Offers structure without being heavy.
- Baking soda: Leavens for an even, tender rise.
- Salt: A pinch amplifies sweetness and keeps the flavor lively.
- Chopped walnuts (optional): Provide textural crunch; omit for a nut-free version.
The Brown Butter Frosting
- Unsalted butter: Browning develops a complex, nutty taste.
- Powdered sugar: Creates a smooth, easily spreadable texture.
- Vanilla extract: Enhances the nutty aroma of the frosting.
- Milk: Adjusts the consistency for just the right pourable texture.
Equipment Check
Gather these before you start:
– 15×10-inch jelly roll pan, or 9×13-inch baking dish for thicker bars
– Mixing bowls (one large, one medium)
– Electric mixer (optional, but helpful for creaming)
– Saucepan for browning butter
– Whisk and sturdy spatula
– Parchment paper, or non-stick spray for lining the pan
Step-by-Step Instructions
1. Prepare Your Pan and Oven
Heat your oven to 375°F (190°C). Line your pan with parchment paper or grease and lightly flour it. This makes removing fully cooled bars much easier. If you’re using a 9×13-inch pan to make taller bars, expect to bake them a little longer—about 5-10 extra minutes.
2. Mix Wet Ingredients
Combine granulated sugar, sour cream, and softened butter in a large bowl. Beat until smooth and creamy. Crack in the eggs, one at a time, mixing well after each addition. Fold in the mashed bananas and vanilla extract until fully combined.
Example: If your bananas are especially large, use just enough to make 1¼ to 1⅓ cups of mashed fruit. Too much banana may make the bars heavy.
3. Mix Dry Ingredients
In a medium bowl, whisk together the flour, baking soda, and salt. This disperses the leavener evenly and prevents pockets of dryness.
4. Combine Mixtures
Add the dry ingredients to the wet bowl. Stir gently with a spatula, stopping as soon as you no longer see streaks of flour. Fold in walnuts if you like a little crunch.
Pro-tip: Overmixing at this point can make the bars tough. Stir just until the mixture comes together.
5. Bake the Bars
Scrape the batter into your prepared pan. Use an offset spatula to spread it evenly. Bake on the center rack for 20 to 25 minutes. The bars are done when their tops are golden and a toothpick poked in the center comes out clean or with a few crumbs.
For thicker bars in a 9×13 pan, begin checking after 27 minutes; add time as needed.
6. Brown the Butter
Just before your bars finish baking, melt unsalted butter in a saucepan over medium heat. The butter will foam, then sputter. Watch for it to deepen from gold to amber, swirling the pan often and scraping the bottom so solids brown evenly. This process takes 4 to 5 minutes. Remove from heat immediately as soon as the butter smells nutty and looks caramel in color.
7. Make the Frosting
Pour the browned butter into a heat-safe bowl. Whisk in powdered sugar, vanilla, and half the milk. Whisk until smooth. Add more milk, a splash at a time, until the frosting is thick but pourable.
Texture check: The ideal frosting will slowly run off a spoon but hold soft peaks. It should glide over freshly baked bars without pooling too fast.
8. Frost the Bars
Once the bars come out of the oven, let them cool just until warm but not hot—about ten minutes. Pour the frosting over, then use a spatula to gently spread it to the edges. The residual warmth helps the frosting sink in and set up with a glossy finish.
Wait until fully cooled before slicing for the cleanest edges.
Tips for Banana Bread Bar Perfection
- Perfect bananas: Black-speckled or nearly all brown bananas pack the best flavor and moisture. If your bananas aren’t ripe yet, roast them in their skins at 300°F for 15 minutes to bring out their sugars.
- Room temperature ingredients: Butter, eggs, and sour cream should all be at room temperature for easier blending.
- Browning butter: Don’t rush this step. Stir constantly and use your nose—the nutty aroma signals readiness.
- Frosting troubleshooting: If your frosting sets too hard before spreading, loosen it with a drizzle of milk and stir again.
Customization Ideas
Banana Bread Bars are endlessly adaptable. Try one or more of these ideas for the next batch:
- Mix-ins: Add mini chocolate chips, toasted pecans, or dried fruit.
- Spices: Fold in a half teaspoon of cinnamon or nutmeg for warmth.
- Decor: After frosting, sprinkle extra walnuts or a dusting of cinnamon on top for a decorative finish.
Storing and Serving
Storing
| Storage | Method | Shelf Life |
|---|---|---|
| Room Temp | Airtight container | 3–4 days |
| Refrigerator | Sealed container | Up to 1 week |
| Freezer | Unfrosted, wrapped tightly | Up to 3 mo. |
Frosted bars may get a little sticky after refrigeration, but the frosting firms up nicely. For the best results, freeze bars unfrosted, then thaw and frost before serving.
Serving Suggestions
- For breakfast: Pair with hot coffee or chai.
- As dessert: Cut into small, neat squares. Add a scoop of vanilla ice cream if you’re feeling festive.
- For gatherings: Serve on a platter. The bars hold shape for party buffets, potlucks, or school events.
Frequently Asked Questions
Can I make these gluten-free?
Yes. Substitute an all-purpose gluten-free flour blend at a 1:1 ratio. Watch your baking time, as some blends may alter the texture slightly.
Do I have to use walnuts?
No. The nuts are optional. For a nut-free version, omit or swap with seeds, such as pumpkin or sunflower.
Is there a dairy-free option?
To bake dairy-free bars, use plant-based butter and coconut or almond yogurt in place of sour cream. For the frosting, plant-based butter and nut or oat milk work well.
Banana Bread Bars with Brown Butter Frosting offer a fresh way to enjoy nostalgic flavors. They’re easy to bake, quick to frost, and disappear fast whenever they’re around. The brown butter frosting alone adds a sumptuous layer that makes these bars feel extra-special, even with simple prep. Whether you serve them warm at brunch or share at a gathering, you’ll find plenty of fans—and probably no leftovers.
Gather your overripe bananas, warm up the oven, and treat yourself to a batch. You may never settle for plain banana bread again.
Banana Bread Bars with Brown Butter Frosting
These decadent banana bread bars with brown butter frosting are moist and sweet. They are perfect for any occasion. You’ll love them!
Ingredients
- 1/2 cup unsalted butter
- 1 teaspoon vanilla extract
- 2 large eggs
- 1/2 cup unsalted butter, softened
- 1 3/4 cups mashed ripe bananas (about 3-4 bananas)
- 2 teaspoons vanilla extract
- 2 cups all-purpose flour
- 1 cup sour cream (can substitute with plain Greek yogurt)
- 1 teaspoon baking soda
- 1/2 cup chopped walnuts (optional)
- 2-4 cups powdered sugar
- 2-3 tablespoons milk or half-and-half
- 3/4 teaspoon salt
- 1 1/2 cups granulated sugar
Instructions
- Preheat the oven to 375°F. Grease and flour a 15x10-inch jelly roll pan or line it with parchment paper. For thicker bars, use a 9x13-inch pan and increase the baking time by 5-10 minutes.
- In a large bowl, beat together the sugar, sour cream, softened butter, and eggs until creamy. Blend in the mashed bananas and vanilla extract.
- In a separate bowl, whisk together the flour, baking soda, and salt. Gradually stir the dry ingredients into the wet ingredients until just combined. Fold in the chopped walnuts, if using.
- Spread the batter evenly into the prepared pan. Bake for 20-25 minutes, until golden brown and a toothpick inserted into the center comes out clean.
- While the bars bake, make the brown butter frosting. Heat the butter in a saucepan over medium heat past the melting point until it boils and turns a delicate brown color. Watch carefully and stir often to prevent burning.
- Remove the butter from the heat and immediately add the powdered sugar, vanilla, and milk. Whisk until smooth. Add more powdered sugar or milk as needed to reach desired consistency - it should be thicker than a glaze but thinner than frosting.
- Remove the bars from the oven and let cool slightly until just warm to the touch. Spread the brown butter frosting evenly over the top of the warm bars.
- Allow the bars to cool completely before cutting and serving. Store leftovers in an airtight container at room temperature for 3-4 days or in the refrigerator for up to a week.