Don’t toss those ripe bananas just yet. These step-by-step instructions will show you how to bake the perfect Banana Cake from scratch using bananas and sour cream. Frosted with Brown Butter Buttercream, this moist and tangy cake is taken up a notch!
Classic brown butter banana cake
Are you looking for a way to use up your ripe bananas? Look no further than this delicious and moist Banana Cake. With the help of ripe bananas and sour cream, this recipe yields a tender, sweet, and fluffy banana cake that rivals any box mix and your everyday banana bread recipe.
What really sets this homemade banana cake recipe apart is the Brown Butter Buttercream. The extra time spent cooking the butter is well worth it to reach the delectable golden brown and deeply flavorful results. It’s so easy too!
What is brown butter?
Brown butter is made by cooking unsalted butter over gentle heat to separate the milk solids. The process transforms regular melted butter into a rich, nutty, and caramel-flavored spread that always elevates the flavors in cookies, cakes, bread, madeleines, and in our case, buttercream frosting!
Is it your first time making brown butter? You’ll get the hang of it in no time. Follow my visual guide to get started and use it on all sorts of recipes, like these Brown Butter Coconut Rice Crispy Treats and Double Dark Chocolate Chip Cookies!
Banana cake ingredients
- Ripe bananas - Make sure the bananas are soft and ripe. Their taste becomes sweeter and stronger as they get riper.
- Sugars - The combination of granulated sugar and light brown sugar flavors the cake perfectly.
- Coconut oil - We need oil to help the cake become moist and rich. Coconut oil won’t make the cake taste like coconut but in case you don't have it on hand, replace it with melted butter.
- Sour cream - This will actually make the cake taste super moist as well as pleasantly tangy and tart. Plain Greek yogurt works well as a substitute.
- Vanilla extract - For warm, rich flavors and balance. Try making your own vanilla extract at home!
- Brown butter buttercream - Made with egg whites, granulated sugar, unsalted butter, and of course, brown butter, this homemade buttercream provides a rich and caramel-like flavor to every bite of cake!
- Garnish - Decorate the banana cake with different layers of toppings and garnishes, like chopped pecans, walnuts, cacao nibs, and whole nuts.
How to make banana cake with sour cream
Step 1: Whisk dry ingredients. In a medium-sized mixing bowl, whisk the flour, baking soda, and salt together. Set the mixture aside.
Step 2: Beat oil and sugars. Add the coconut oil, granulated sugar, and brown sugar to a large mixing bowl and beat until light and fluffy.
Step 3: Add the egg. Next, add the egg and continue beating while scraping down the sides of the bowl as needed.
Step 4: Add the remaining wet ingredients. Add the sour cream and the mashed bananas. Gently mix to combine.
Step 5: Mix the dry and wet ingredients. In the bowl with the wet mixture, add the dry ingredients and mix until a thick and sturdy batter forms (similar to a pancake batter). Be sure not to overmix!
Step 6: Bake. Pour the cake batter into your prepared cake pan and bake until a toothpick inserted in the middle comes out clean.
Step 7: Let it cool. Be sure to let the cake cool completely on a cooling rack before moving on to assembly and decorating.
How to make brown butter buttercream
Step 1: Assemble the double-boiler. Bring a saucepan of water to a boil. Add the sugar and egg whites to the bowl of a standing mixer and set it on top of the saucepan. The bottom of the bowl should not be touching the water.
Step 2: Whisk egg whites and sugar over the heat. Whisk the bowl of egg whites and sugar together over the hot water until the sugar dissolves and the mixture’s temperature reaches 165ºF. When it’s ready, return the bowl to your standing mixer.
Step 3: Whisk to form soft peaks. Start at low speed and whisk, gradually increasing speed, until soft peaks form and the mixture cools.
Step 4: Add both kinds of butter. Switch out the whisk for the paddle attachment and begin creaming in the brown butter and regular butter a little bit at a time until a glossy and smooth frosting forms. Stop mixing and set the bowl aside.
Assembling the cake
Step 1: Frost. Once the cake has cooled, spread as much of the buttercream over the surface of the cake as you like.
Step 2: Decorate. Feel free to use a spoon or offset spatula to texturize the buttercream (I used a small spoon to create swirls).
Step 3: Garnish. Don’t forget the toppings! Finish your cake with layers of toppings, like pecans, walnuts, and cacao nibs. Enjoy the cake chilled or at room temperature.
Tips to make the best banana cake
- Before making the butterecream, refrigerate the brown butter before you start making your cake.
- For a smaller, single-layer cake, you can bake the cake in an 8-inch cake pan. You’ll just need to reduce the cooking time a bit.
- Use room temperature eggs and butter for the best results and even baking.
- Don’t overmix your batter! An overworked batter may result in a tough, chewy cake.
Want to keep things simple? Instead of the buttercream, decorate the banana cake with cream cheese frosting.
Frequently asked questions
While both of these banana-forward baked goods are a great way to use over-ripened bananas, they’re not quite the same. Banana cake generally has a tender, moist, and fluffy texture, while banana bread is usually heavy and crumbly. Not to mention, banana cakes are typically frosted and banana bread is not.
Absolutely! Divide the batter into a lined muffin tin and bake at 350ºF for 20-25 minutes or until a toothpick inserted in the middle comes out clean. As always, let the cupcakes cool completely before frosting.
The batter yields a delightful density somewhere right in the middle! The baked cake is sturdy, pleasantly bouncy, and melt-in-your-mouth tender.
What can I substitute for the sour cream?
Sour cream and full-fat plain Greek yogurt can be used interchangeably in many baked goods, including this banana cake. Baking cakes with sour cream or Greek yogurt helps them taste rich and moist.
This most likely happened because your cake was underbaked. Be sure to bake your cake all the way through. Also, avoid opening and closing the oven door and moving the cake pan around while baking.
To freeze, make sure your cake has cooled completely, and then wrap it in a couple of layers of plastic wrap and a layer of foil or a freezer-safe bag. Freeze for 3 to 4 months. When you’re ready to enjoy the cake, let it thaw at room temperature for 3 to 4 hours and then frost.
More ripe banana recipes
- Banana Bread with a Crunch
- Banana Cake with Almond Buttercream
- Coconut Banana Bread Cupcakes
- Sourdough Walnut Banana Bread
More cakes with buttercream
- The Ultimate Carrot Cake
- Berry Buttercream and Lemon Poppyseed Cake
- Lemon Cake with Mascarpone Buttercream
Banana Cake with Brown Butter Buttercream
- Stand Mixer with Paddle and Whisk Attachment
- 6 inch Cake Pan for a tall Single Layer Cake
- 8 inch Cake Pan for a shorter Single Layer Cake
- Parchment Paper
- Cooling Rack
- 1.5 (180 g) Ripe Bananas, mashed
- ⅓ Cup (67 g) Granulated Sugar
- ¼ Cup (55 g) Light Brown Sugar, packed
- ¼ Cup (55 g) Coconut Oil
- 1 Large Egg, room temperature
- ¼ Cup (58 g) Sour Cream
- 1 tsp Vanilla Extract
- 1 Cups (125 g) All-Purpose Flour
- ½ tsp Baking Soda
- ¼ tsp Salt
Brown Butter Buttercream
- 1.5 (45 g) Egg Whites
- ½ Cup (100 g) Granulated Sugar
- ⅓ Cup (75 g) Unsalted Butter , Room Temperature
- ⅓ Cup (75 g) Brown Butter , Room Temperature
- Walnuts, Pecans, and Cacao Nibs
- Preheat your oven to 350 degrees Fahrenheit.
- Combine all your dry ingredients – flour, baking soda and salt in a medium-sized bowl, give it a whisk and set aside.
- Add the coconut oil and sugars into a large bowl and beat together until well mixed.
- Add egg, then scrape the bowl making sure ingredients are mixed well. Then add the sour cream, mix and finally add the mashed bananas mixing until combined.
- Add the dry ingredients, and mix until just combined.
- Pour batter into a greased 6 inch cake pan and bake for 40-45 minutes. For a shorter single layer cake, you can always instead bake your cake in an 8 inch cake pan for a shorter amount of time. Make sure to check that the cake is fully baked with a toothpick before removing from the oven and allowing to cool completely before assembling.
Brown Butter Buttercream
- Add your sugar and egg whites in the bowl of a stand mixer and place over a saucepan of boiling water.
- Make sure that your bowl is not touching the hot water! Your goal is to simply whisk the egg whites and sugar together over a gentle heat until the sugar has completely dissolved, then attach your bowl back to the standing mixer. The temperature should read 165 F before it’s ready to be removed from the heat.
- Whisk mixture starting at a low speed and gradually increase until soft peaks form and the mixture has cooled. Switch to using your paddle attachment, then start adding your brown butter and regular butter bit by bit.
- When you’ve reached the point where the buttercream is glossy and smooth, stop the mixer and set aside for assembling.
- Add as much of your brown butter buttercream on top of the cake and spread evenly. Utilizing a spoon or an offset spatula, create swirls and swoops to your liking into the buttercream! I used a small spoon to create the swirls you see below. Add the decoration of your liking on top! I added a couple different layers of toppings, starting with some chopped pecans and walnuts, cacao nibs and then whole nuts to add for a pleasing aesthetic.