Sourdough Banana Cake
This sourdough banana cake is moist, slightly tangy, and has plenty of warm spices.
This is a true cake: a dessert, not a breakfast. (Not that I would judge you for having a slice in the morning!). You can grab that recipe here if you’re looking for banana bread.
Sourdough Banana Cake

Ingredients
Cake
- 2 very ripe bananas mashed
- ½ cup granulated sugar
- ½ brown sugar
- ½ cup vegetable oil
- 2 eggs
- 1 teaspoon vanilla
- 2 cups flour
- 1 teaspoon baking soda
- ½ teaspoon salt
- ½ cup sourdough starter discard or unfed
Frosting
- 4 ounces cream cheese room temperature
- 6 tablespoons butter room temperature
- 1 teaspoon vanilla
- 2½ cups powdered sugar
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Instructions
Make the Cake
- Preheat oven to 350 degrees with the rack in center. Prepare a 9 inch round or square cake pan with cooking spray or shortening dusted with flour
- Beat the oil, sugars, and banana in a large mixing bowl with an electric mixer on medium speed. Add the egg and vanilla, mix until combined.
- Combine the flour, baking soda, and salt in a separate large mixing bowl. Add the dry ingredients 1/3 at a time, mixing on low until just combined after each addition. Add the sourdough starter and stir in by hand.
- Pour the batter into the prepared cake pan and bake in the preheated oven for 45-50 minutes, or until a cake tester inserted into the center comes out clean. Carefully turn cake out onto cooling rack. Allow to cool completely before frosting.
- Cut into wedges or squares to serve. Cover and refrigerate any leftovers for up to 5 days.
Make the Frosting
- Beat the cream cheese and butter in a large mixing bowl until smooth. Add the vanilla and mix until combined. Add half the powdered sugar and beat on low. Add the remaining powdered sugar and beat on low until combined, then increase the speed to medium and beat for 1 minute.
Notes
Nutrition
🧂 Ingredients
You’ll need the following for this yummy snack cake:
- very ripe bananas
- sugar
- brown sugar
- vegetable oil
- eggs
- vanilla
- flour
- baking soda
- salt
- sourdough starter
- non-stick baking spray

- square or round cake pan
- hand mixer
- spatula
🥫 Storage instructions
Cover and refrigerate any leftovers for up to 5 days. The cake freezes well unfrosted.

👩🏻🍳 Expert tips
- Don’t overmix the batter.
- This recipe is quite sweet and you can safely reduce the sugar by about 1/3 and still get a good result.
- Make sure your bananas are very ripe and soft or they won’t properly incorporate into the batter.
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By Katie Shaw

Katie shares simple, reliable recipes from her home in Virginia, where she lives with her husband, three daughters, a chocolate lab, and over thirty chickens.
I use to make this once a week. I always add three bananas. It’s just an incredible morning quick bite with a cup of joe! The best flavor and has become many anniversary gifts. This recipe can’t be beat! I’m a true fan!
Hey Cindy! I’m so touched that you even gift it for anniversaries—what a thoughtful, homemade treat to share. Thank you so much for being a true fan and for making this recipe a part of your weekly routine. 🙂
After seeing the notes about how it is more of a bread than cake texture, I did add two teaspoons of baking powder (like most of my sourdough cake recipes call for) and it was amazing. I also always use coconut oil baking sweets. I have since added some walnuts and dark chocolate to the batter and have swapped the sweetener in the cream cheese frosting for honey or maple syrup. Have never thought that banana cake was a thing, but since I live somewhere we grow our own delicious bananas, I bake banana bread and banana muffins and now love the addition of this cake.
Rose up beautifully. More of a quick bread texture, which pairs perfectly with the cream cheese frosting.
thank you jolene! i’m so happy you liked it! frosting for breakfast, right 🙂
Have made a lot of banana cakes and breads over the years as it is my husbands favorite. This is excellent – light, fluffy and moist with good banana flavor. Reduced the sugars slightly and subbed the white sugar. Used coconut oil for 1/2 of oil. Added toasted walnuts. My boys gave it two thumbs up! So great to make instead of layer cake when traveling with it. So happy to incorporate sourdough into one of our favorite family treats!
Good flavor, doubled for 9 X 13. Rose up beautifully. This is dense, more like a quick bread than a cake. Next time I’ll do in loaf pan and skip icing.
How would you recommend a long ferment process? Only mixing flour, starter, oil together for 12-24 hours?
Hi! I was looking for a banana cake recipe that also used sourdough discard and I found yours! Excited to try it! I am confused by the pan sizes mentioned – you say use either a 9″ round or square. Those two pans are not really equivalent in volume and swapping them will make for very different baking times and cake size. (a 9″ round has 63.5″ area and holds approx 8 cups of batter. A 9″ square is 81″ area and holds 10cups batter) Which shape pan do you typically use with the baking time indicated on the recipe for the best success? Thanks so much!
Hey Karyn I use a round!
Thanks! I had so much discard I didn’t want to waste – so I actually tried doubling this and used a 9×13 pan and it worked great!! It’s a very yummy recipe!
This was absolutely delicious! Thank you for sharing this recipe.