Irresistible Banana Bread Bars With Brown Butter Frosting

We’ve all been there: a bunch of bananas sitting on the kitchen counter, adorned with more brown spots than yellow. While your first thought might be to whip up a standard loaf of banana bread, we invite you to try something truly special. Let us introduce you to a recipe that will elevate those overripe bananas into a dessert that is nothing short of heavenly: our Banana Bread Bars with Brown Butter Frosting.

This is far more than your average banana bake. We have captured the comforting essence of a classic banana cake and transformed it into soft, chewy bars by baking it in a sheet pan. The crowning glory, however, is the frosting. We forgo a simple glaze in favour of a rich, nutty brown butter frosting that imparts an incredible depth of flavour. This single element transforms a humble snack into a truly memorable dessert. Prepare to discover your new favourite way to use up those bananas!

Why You’ll Love This Recipe

• Supremely Soft and Delicious: The combination of very ripe bananas and soured cream ensures these bars have an unbelievably moist and tender texture. It’s the perfect recipe for a moist banana snack cake, bursting with sweet banana goodness in every single bite.
• The Wonder of Brown Butter: The aromatic, caramelised scent of the brown butter frosting is simply irresistible. It creates a beautiful contrast with the sweetness of the banana, resulting in a sophisticated flavour that feels wonderfully indulgent.
• Made for Sharing: As this is an easy banana sheet cake, it’s brilliant for feeding a group. Whether you’re heading to a potluck, contributing to a bake sale, or treating your family, these bars are simple to slice and serve.
• Beautifully Simple to Make: This recipe relies on everyday ingredients you likely already have. We provide clear, step-by-step instructions, including how to master brown butter, so bakers of all levels can achieve fantastic results with ease.
• Wonderfully Versatile: These bars are a true delight at any time. Enjoy one for dessert, as a comforting afternoon pick-me-up with a cup of coffee, or even as a little breakfast indulgence.

Ingredients

• 250g plain flour
• 1 tsp bicarbonate of soda
• ½ tsp salt
• ½ tsp ground cinnamon
• 115g unsalted butter, softened
• 200g granulated sugar
• 50g light brown sugar, packed
• 2 large eggs, at room temperature
• 1 tsp vanilla extract
• 3-4 very ripe large bananas, mashed (about 350g)
• 60g soured cream or full-fat Greek yoghurt
• 115g unsalted butter
• 300g icing sugar, sifted
• 1 tsp vanilla extract
• 2-3 tbsp milk or double cream
• A pinch of salt

Before we get started, it’s always a good idea to have all your ingredients measured and ready to go. We’ve separated the list into the components for the banana bars and for that show-stopping brown butter frosting. This simple preparation makes the entire baking process feel calm and effortless.

• For the Banana Bars:
• 250g plain flour
• 1 tsp bicarbonate of soda
• ½ tsp salt
• ½ tsp ground cinnamon
• 115g unsalted butter, softened
• 200g granulated sugar
• 50g light brown sugar, packed
• 2 large eggs, at room temperature
• 1 tsp vanilla extract
• 3-4 very ripe large bananas, mashed (about 350g)
• 60g soured cream or full-fat Greek yoghurt
• For the Brown Butter Frosting:
• 115g unsalted butter
• 300g icing sugar, sifted
• 1 tsp vanilla extract
• 2-3 tbsp milk or double cream
• A pinch of salt

Step-by-Step Guide: Making the Perfect Banana Bars

Crafting these delectable bars is a surprisingly simple affair. We will walk you through every stage, ensuring you end up with a beautifully moist cake with a soft, delicate crumb. This is a truly wonderful banana bars recipe that is suitable for everyone, from beginners to seasoned bakers.

1. Prepare Your Tin and Oven

First, let’s get everything in order. We start by preheating the oven to 175°C (160°C Fan / Gas Mark 4), as an accurate temperature is vital for a consistent bake. Then, prepare a 9×13 inch (23×33 cm) baking tin by greasing it well with butter or a baking spray. For easy removal later, we suggest lining the tin with baking parchment, allowing it to overhang on the long sides to create handles.

2. Combine the Dry Ingredients

In a medium bowl, it’s time to mix our dry ingredients. Add the 250g of plain flour, 1 tsp of bicarbonate of soda, ½ tsp of salt, and ½ tsp of ground cinnamon. Use a whisk to combine them thoroughly. This simple action helps to aerate the flour and ensures the raising agent and spice are evenly distributed throughout the batter.

3. Mix the Wet Ingredients

Now we move on to the base of our cake. In a large bowl, using a stand mixer with a paddle attachment or a handheld electric mixer, cream together the 115g of softened unsalted butter with the 200g of granulated sugar and 50g of light brown sugar. Beat on a medium-high speed for 2-3 minutes until the mixture becomes pale, light, and airy. This step is crucial for achieving a light-textured cake.

Next, add the 2 large eggs, one at a time, beating well after each addition to ensure they are fully incorporated. Follow with the 1 tsp of vanilla extract. Remember to scrape down the sides of the bowl. On a low speed, gently mix in the mashed bananas and the 60g of soured cream until they are just combined. The mixture might look slightly split, but that’s perfectly normal and it will come together.

4. Bring it All Together & Bake

Gently add the dry ingredients to the wet mixture in two or three stages. Mix on the lowest speed possible, just until you can no longer see streaks of flour. It is vital not to overmix the batter, as this can lead to a tough and dense cake instead of a soft one.

Carefully pour the finished batter into your lined tin, using a spatula to smooth it into an even layer right to the corners. Bake in the preheated oven for 25-30 minutes. You’ll know it’s ready when a skewer inserted into the centre comes out clean. Allow the cake to cool completely in the tin on a wire rack. Please don’t be tempted to frost it while it’s warm, as this will result in a runny, melted frosting!

The Secret to a Sublime Brown Butter Frosting

This frosting is what elevates the banana bars from simply delicious to absolutely extraordinary. If you’re new to making brown butter, you’re about to discover a wonderful culinary secret. It provides a toasted, nutty, almost caramel-like richness that is utterly divine and the perfect counterpoint to the sweet banana cake.

What is Brown Butter?

Brown butter, known as beurre noisette in French cooking, is butter that has been gently heated until the milk solids separate and toast. As the butter melts, the water content cooks off and the milk solids fall to the bottom of the pan. With continued heat, these solids turn a beautiful amber-brown, releasing a wonderfully fragrant, nutty aroma. For a more scientific explanation of this magical process, resources like King Arthur Baking offer great insight.

How to Make the Brown Butter Icing for Banana Bars

Creating this icing is easy, but it requires your undivided attention for a few key moments. Just follow our steps for a flawless result:

1. Melt the Butter: In a small, light-coloured saucepan, melt the 115g of unsalted butter over a medium heat. A pale pan makes it much easier to monitor the colour change.
2. Watch it Bubble: The butter will first melt, then start to foam and bubble energetically. Swirl the pan from time to time to encourage even cooking.
3. Look for Brown Specks: After a few minutes, the foaming will die down. You will notice golden-brown specks forming at the bottom and the butter will take on an amber hue, smelling incredibly nutty. This is the magic moment! Take the pan off the heat immediately to stop the process.
4. Combine and Whisk: Pour the hot brown butter, including all those flavourful toasted bits, into a heat-resistant bowl and let it cool slightly. Add the 300g of sifted icing sugar, 1 tsp of vanilla, a pinch of salt, and 2 tablespoons of milk. Whisk until everything is well combined and you have a smooth, creamy frosting. If it feels too stiff, add another tablespoon of milk until you have a thick yet spreadable consistency.
5. Frost the Bars: When the banana cake has cooled down completely, pour the frosting over the top. Use an offset spatula or the back of a spoon to spread it out evenly. Allow the frosting to set for at least 30 minutes before you slice and serve your delicious bars.

Tips for the Best Banana Dessert Bars

To make sure your banana bars turn out perfectly every single time, here are some of our most valuable tips.

• Use Very Ripe Bananas: For the best flavour, your bananas should be heavily speckled or even mostly black. Overripe bananas are significantly sweeter and have a more concentrated banana taste, which truly shines in the finished bake.
• Don’t Overmix the Batter: It’s a point worth repeating! To achieve that sought-after soft and tender crumb, only mix the flour until it is just incorporated.
• Add Some Texture: For a little extra crunch and flavour, consider folding in around 100g of chopped walnuts, pecans, or even some chocolate chips. With these additions, the bars take on a new character, becoming more like decadent banana blondies with frosting.
• Patience is Key: We can’t stress this enough: your cake must be completely cool before you add the frosting. A warm cake will simply melt the icing into a greasy layer.

These bars are a wonderful way to finish a family meal. A sweet treat is always a welcome sight, whether it follows a hearty main like our Creamy Garlic Penne Pasta or something lighter.

FAQ

The Ultimate Banana Treat Awaits

And there you have it – our complete guide to what we truly believe are the best banana dessert bars you will ever make. The marriage of a deeply moist, cinnamon-kissed banana cake with the rich, nutty notes of brown butter frosting is a flavour combination that is simply second to none. It’s an easy recipe that yields incredibly impressive results.

So, the next time you find yourself with a bunch of overripe bananas, we encourage you to look beyond standard banana bread. Make a tray of these incredible Banana Bread Bars with Brown Butter Frosting instead. We are confident you will be delighted. Are you ready to begin? Find those spotty bananas, preheat your oven, and let’s get baking! We would be thrilled to hear how you get on, so please feel free to leave a comment below and share your results.

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Prep: 20 mins
Cook: 30 mins
Serves: 16-20

Ingredients

• For the Banana Bars:
• 250g plain flour
• 1 tsp bicarbonate of soda
• ½ tsp salt
• ½ tsp ground cinnamon
• 115g unsalted butter, softened
• 200g granulated sugar
• 50g light brown sugar, packed
• 2 large eggs, at room temperature
• 1 tsp vanilla extract
• 3-4 very ripe large bananas, mashed (about 350g)
• 60g soured cream or full-fat Greek yoghurt
• For the Brown Butter Frosting:
• 115g unsalted butter
• 300g icing sugar, sifted
• 1 tsp vanilla extract
• 2-3 tbsp milk or double cream
• A pinch of salt

Instructions

1. Preheat oven to 175°C (160°C Fan). Grease and line a 9×13 inch (23×33 cm) baking tin with baking parchment, leaving an overhang to act as handles.
2. In a medium bowl, whisk together the plain flour, bicarbonate of soda, salt, and ground cinnamon.
3. In a separate large bowl, using an electric mixer, cream the softened butter with the granulated and light brown sugars for 2-3 minutes until pale and fluffy.
4. Beat in the eggs one at a time, followed by the vanilla extract. On low speed, mix in the mashed bananas and soured cream until just combined.
5. Add the dry ingredients to the wet mixture in two stages, mixing on low speed only until no streaks of flour remain. Do not overmix.
6. Pour the batter into the prepared tin and spread evenly. Bake for 25-30 minutes, or until a skewer inserted into the centre comes out clean. Let the cake cool completely in the tin.
7. To make the frosting, melt 115g unsalted butter in a light-coloured saucepan over medium heat. Continue cooking as it foams, swirling the pan occasionally, until golden-brown specks form at the bottom and it smells nutty.
8. Immediately remove the brown butter from the heat and pour it into a heat-resistant bowl to cool slightly.
9. Add the sifted icing sugar, vanilla extract, a pinch of salt, and 2 tbsp of milk to the brown butter. Whisk until smooth and creamy. If it’s too thick, add more milk, a little at a time, to reach a spreadable consistency.
10. Once the cake is completely cool, spread the frosting evenly over the top. Allow the frosting to set for at least 30 minutes before slicing and serving.