Try these banana bread brownies with brown butter frosting.
The banana bread layer is dense and moist.
The frosting is rich, sweet, and decadent. The combination is incredible.
These banana bread brownies are moist, dense, and full of delicious banana flavor.

Let's talk about the frosting.....
The frosting is what seals the deal. It is rich, buttery, sweet, and creamy.
I could eat it for days if my waistline would let me. It is freakin' AWESOME!!! (Like lick the bowl good.)
The combination of the frosting layered on the banana bread bars tastes like banana's foster.
You are going to love it!
Watch how to make banana bread brownies

Ingredients for banana bread brownies
You will need the following ingredients to make banana bread brownies:
- baking soda
- butter- Salted or unsalted butter will work. Soften to room temperature.
- sour cream- You can substitute with plain or vanilla real Greek yogurt.
- bananas- The riper the bananas, the better these banana bars will be.
- vanilla extract
- eggs
- sugar
- salt
- all purpose flour

Steps to make brownies
Follow these steps to make the banana bread brownies.
- In a large bowl, beat together sugar, sour cream, eggs, and butter until creamy.
- Blend in bananas and vanilla.
- Add flour, baking soda, and salt. Mix until completely blended.
- Spread into pan and bake for 30 to 35 minutes or until golden brown. (Be careful not to overcook. You don't want to dry them out. Check with a toothpick to make sure they are done. They will also continue to bake as they rest in the pan.) In the last 10 minutes of baking, make the frosting.

Ingredients for brown butter frosting
You will need the following ingredients to make the brown butter frosting.
- powdered sugar
- vanilla extract
- butter-I prefer salted to cut the sweetness a bit.
- whole milk

Steps to make the brown butter frosting
Follow these steps to make brown butter frosting:
- Slice butter and add to a medium sized sauce pan.
- Cook butter over medium until it reaches a toasty brown color. Watch carefully and stir the entire cooking time to prevent it from scorching. (It only takes a second to burn towards the end of the cooking process if you are not stirring.)
- Once the butter turns a toasty brown color, reduce heat to a simmer. Immediately add powdered sugar, vanilla extract, and milk. Mix until smooth. It should be thicker than a glaze but a little thinner than a frosting.
- Spread on Banana Bread while the bread is still warm. Allow to completely cool before serving. Cut into bars.
Note: Cool the brownies at least 2 hours before serving. Do not cut the banana bread brownies before completely cooling. Allowing the brownies to completely cool retains the moisture.

How do you store the banana bread bars?
Store the banana bread bars in an air tight container at room temperature for 3-4 days. You can refrigerate them, but they will loose some of their moisture.
If you are serving them outdoors in high heat, keep them cool in the cooler before serving or the frosting will melt.
If you like this recipe, try some of these:
- Chocolate Eclair Cake
- Coconut Cream Poke Cake
- Brown Sugar Bourbon Fudge
- Chocolate Cherry Sheet Cake
- Banana Pudding with Sour Cream
Please leave me a comment below if you make these banana bread brownies and tell me what you thought about it. I would love to hear back, and so would my readers.
Also post your picture of your dessert on Instagram or Facebook, and tag @aforkstale with #aforkstale hashtags! I will share with my followers! xoxo!

Banana Bread Brownies with Brown Butter Frosting
Ingredients
- 1 ½ cup sugar
- 1 cup sour cream
- 2 eggs
- ½ cup butter softened
- 1½ cup bananas mashed (3 to 4 bananas)
- 1 teaspoon vanilla extract
- 2 cups all purpose flour
- 1 teaspoon baking soda
- ¾ teaspoon salt
Brown Butter Frosting
- ½ cup butter
- 4 cups powdered sugar
- 2 teaspoons vanilla
- 3 tablespoons whole milk
Instructions
Banana Bread Brownies
- In a large bowl, beat together sugar, sour cream, eggs, and butter until creamy.1 ½ cup sugar, 2 eggs, ½ cup butter
- Blend in bananas and vanilla.1½ cup bananas, 1 teaspoon vanilla extract
- Add flour, baking soda, and salt. Mix until completely blended.2 cups all purpose flour, 1 teaspoon baking soda, ¾ teaspoon salt
- Spread into 9x 13 greased and floured baking pan. Bake at 375 for 30 to 35 minutes or until golden brown. (Be careful not to overcook. You don't want to dry them out. Check with a toothpick to make sure they are done. They will also continue to bake as they rest in the pan.)
- In the last 10 minutes of baking, make the frosting.
Brown Butter Frosting Instructions
- Slice butter and add to a medium sized sauce pan.½ cup butter
- Cook butter over medium until it reaches a toasty brown color. Watch carefully and stir the entire cooking time to prevent it from scorching. (It only takes a second to burn towards the end of the cooking process if you are not stirring.)
- Once the butter turns a toasty brown color, reduce heat to a simmer. Immediately add powdered sugar, vanilla extract, and milk. Mix until smooth. It should be thicker than a glaze but a little thinner than a frosting.4 cups powdered sugar, 2 teaspoons vanilla, 3 tablespoons whole milk
- Spread on Banana Bread while the bread is still warm.
- Allow to completely cool before serving. Cut into bars.
Kim Hardesty
These sound GREAT, Katie. My grandmother passed down a cookie with a browned butter icing. It's one of my favorite recipes. I'm sure this will be a favorite of my kids, too. Thank you for sharing!
Donna Ellison
October 16,2018
I made this recipe today and it is awesome! Thank you so much.
Vivian
The Brown Butter Frosting is totally awesome. I made only 1/2 of the recipe and instead of using 2 cups after cutting the recipe in half I only used 1 cup of powdered sugar and added a couple drops of almond extract in addition to the vanilla. I also grounded up some pecan nuts and after frosting my banana bread muffin I dipped it into the nuts. It tasted like caramel frosting. This is definitely my go to frosting. Thanks.
Mikayla
Great concept, I truly love brown butter frosting and found these Banana bread brownies not only were a perfect after dinner treat but made a very good breakfast with my morning coffee.
Jessica
A friend shared this recipe with me a while ago and I just got around to trying it. I'm kind of kicking myself in the butt about it because they are sooooo good. I added some walnuts for texture and next time plan to try pecans instead. Can't wait!
Devan
Katie this sounds like an absolute winner. I'm a sucker for anything with brown butter and I love how you used it in the frosting. Can't wait to try this!
Kathryn
These banana bread bars are heavenly! The brown butter frosting is my favorite and takes these bars to a new level of deliciousness!
Allyssa
Thanks a bunch for this amazing idea! Will surely have this again, it turned out really delicious and very easy to make! Loved it!
Veronika
I can't believe I'd never made banana bread brownies until now! This was an amazing dessert, especially with the brown butter frosting. The whole family enjoyed it as well!
Heather
Love this! The brown butter frosting was everything and more and totally made these brownies extra special.
Tristin
Very impressed with these banana bread brownies and the brown butter frosting was to die for!! YUM!!
Marie
These bars perfectly combine the comforting flavors of banana bread with the brown butter frosting that is perfection! --I'm obsessed and I want to use it on cupcakes and in layered cakes, too!
LaKita
These banana bread bars are so delicious and amazing. The brown butter frosting was my favorite part, yum!
Maiko
I made a little tweak in ingredients and make it plant-based, it turned out pretty good! I used vegan butter, almond milk, and coconut yoghurt instead of sour cream. The brownies came out nicely and tasted amazing. I'm making them for when my friends come over!
Teresa
Excellent portions on the ingredients. The bars themselves need some seasoning; next time I will add some cinnamon and nutmeg. They were just a wee big bland without it. Brown butter frosting amazing as is!! I will make again!
Joy
I followed the directions exactly and have made this a few times already. It is absolutely delicious and everyone who has tried it has loved it. Thank you for sharing!