Sourdough Walnut Banana Bread is not your average banana bread recipe! Made with sourdough discard, the walnut-loaded loaf has a tangy twist of flavor and moist texture.
Easy sourdough discard banana bread
Instead of throwing away the discard while you’re feeding your sourdough starter, put it to use in this Sourdough Walnut Banana Bread. The baked loaf ends up with added moisture and a delectable tangy flavor in comparison to regular banana bread. It’s also loaded with walnuts and topped with a sweet oat crumble to take every bite to the next level!
I hate to see sourdough discard go to waste, especially when it can give your bakes some seriously exceptional qualities. Whether it’s used to make focaccia bread, garlic bread, a regular sourdough loaf, Sourdough Grilled Cheese or banana bread, sourdough discard is solely responsible for providing balance and an exceptional rise.
Forget about food waste and put the sourdough discard and brown, spotty bananas to use in this sourdough banana bread. The slices are the perfect pick-me-up during breakfast or for an afternoon snack!
Ingredients and substitutions
Banana bread doesn’t have to be boring! This unique version features a mix of unexpected ingredients and a sweet oat crumble on top. Here’s what you need to make this sourdough banana bread recipe:
- Sourdough discard - Sourdough starter is easy to make at home using flour and water. If you don’t have one already, buy one instead or see if your family and friends have any to spare.
- All purpose flour - I haven’t tested it, but this recipe should also work with a 1:1 mix of all purpose flour and whole wheat flour.
- Bananas - Make sure they’re overripe bananas - old and spotty! Ripe bananas are easier to mash, have a stronger banana flavor, and blend into the bread dough with ease.
- Brown sugar - Just like chocolate chip cookies, brown sugar adds that deep, molasses-like flavor to banana bread rather than a white sugar addition.
- Bourbon extract - An optional, but outstanding addition! The rich and deep flavors pair so well with brown sugar and bananas.
- Chopped Walnuts - For some crunch and texture. You can leave them out if you have an aversion to nuts or replace them with chocolate chips, pumpkin seeds, or more fun add-ins.
- Oat crumble - This sweet and crunchy banana bread topping is easy to make using rolled oats, cold butter, flour, and sugar.
A note on using Sourdough Starter Discard
If you tend to feed your starter every day, you most likely have quite a bit of active sourdough starter that you are getting rid of after each feeding. Usually, when I have sourdough discard starter, I'll put my leftovers in the fridge for a day or two in case I end up using those leftovers for a recipe!
Never made a starter before? No problem! Head on over to this guide for making your own sourdough starter at home to get started! Then you can hop over to my post detailing How to make Sourdough Bread.
How to make sourdough walnut banana bread
These easy-to-follow steps will show you how to make walnut banana bread with a moist and tender crumb:
Step 1: Start with the oat crumble. Pulse the oats in a food processor. Combine them with the sugar, flour, and sea salt in the bowl of a stand mixer. Add the cold butter and mix until crumbly. Set it aside in a small bowl while you work on the bread.
Step 2: Mix the dry ingredients. Whisk the flour, baking powder, and salt together in a medium bowl.
Step 3: Mix the wet ingredients. Mash the bananas with a fork in a separate bowl. Add in the sourdough discard, vanilla extract, and bourbon extract to the mashed bananas.
Step 4: Cream the butter. Cream the butter and sugar together in a large mixing bowl of a standing mixer with a paddle attachment. Then add the eggs one at a time.
Step 5: Finish the dough. Gently beat the wet ingredients into the butter, sugar, and egg mixture. Next, add the dry flour mixture in two stages, scraping the bowl between additions. Finish by folding the walnuts into the dough.
Step 6: Bake, cool, and enjoy. Transfer the dough into your prepared loaf pan and sprinkle the oat crumble on top. Bake in the preheated oven until a toothpick inserted in the center comes out clean. Allow the bread to cool completely on a wire rack or cooling rack before slicing and enjoying!
Tips and variations
- Measure by volume - Measure the bananas by volume/weight instead of the number of bananas. A lot of recipes will mention using a certain number of ripe bananas, but I've found that using a specific unit of measurement will give you the best, most consistent results every single time.
- Prepare your loaf pan - Coat the bottom and sides of your loaf pan with butter. You can also line it with a piece of parchment paper, allowing the excess to run up the sides to act as handles.
- More banana bread add-ins - Not into walnuts? Swap them for chopped pecans, pumpkin seeds, chocolate chips, cinnamon, nutmeg, or raisins.
- Don’t slice until it’s completely cool - The warm banana bread will crumble if it’s sliced too early.
Frequently asked questions
As you continue to feed a sourdough starter with fresh flour and water, some of the starter must be thrown away or else it’ll become overly acidic and too big and unmanageable. The starter you throw away is known as the discard.
You can quicken the ripening process by placing the bananas in a brown paper bag for a few days.
You can, but it’s best to let them thaw first. They’ll be easier to mash and work with this way.
Place the cooled loaf or slices of banana bread in an airtight container. Store at room temperature for 3 or 4 days, or in the fridge for up to 1 week.
Yes, banana bread freezes very well. Wrap the loaf or individual slices in plastic or aluminum foil and freeze in a ziplock bag for up to 3 months.
For more tips on how to store banana bread, head over to my in-depth guide!
More Great Sourdough Recipes
As always, I love seeing your creations and hearing from you! If you try the recipe for this Sourdough Walnut Banana Bread, please leave a review or share your creation with me on social media! You can find me on Instagram, Facebook, Youtube and Pinterest - for more delicious recipes sent straight to your inbox, sign up for my newsletter!
Sourdough Walnut Banana Bread
- Food Processor
- Electric Mixer
- 9x5 Loaf Pan
Banana Bread with Sourdough Starter
- 150 g (1 ¼ cups) All Purpose Flour
- 2 teaspoon Baking Powder
- ¾ teaspoon Sea Salt
- 215 g (About 2 bananas ) Ripe Bananas
- 150 g (⅔ cups) unsalted butter, room temperature
- 185 g (¾ cup + 2 Tablespoons) brown sugar
- 2 large eggs
- 200 g (1 cup) sourdough discard
- 1 teaspoon vanilla extract
- 1 teaspoon bourbon extract
- 150 g (1 ⅓ cup) chopped walnuts
- 50 g (⅔ cup) Oats
- 50 g (¼ cup) Brown Sugar
- 50 g (¼ cup) Cold, Unsalted Butter
- 4 g (¼ teaspoon) Sea Salt
- 50 g (½ cup) All Purpose Flour
- Using a food processor, pulse oats until they’ve slightly been broken up50 g Oats
- Place the oats, sugar, flour and sea salt in the bowl of a stand mixer and mix using the paddle attachment.50 g Brown Sugar, 50 g All Purpose Flour, 4 g Sea Salt
- Slowly add cold bits of butter and mix until crumbly.50 g Cold
- Place crumble in an air-tight container and place in the fridge until you’re ready to use!
Banana Bread with Sourdough Starter
- Preheat the oven to 350°F. In a medium bowl add the flour, baking powder and salt and whisk together to combine.150 g All Purpose Flour, 2 teaspoon Baking Powder, ¾ teaspoon Sea Salt
- In a separate bowl add the bananas and use a fork or potato masher to mash. Add the sourdough, vanilla and bourbon extract, stirring until evenly mixed.215 g Ripe Bananas
- Place the butter and sugar into the bowl of a standing mixer, and cream together using a paddle attachment until light and fluffy. This should take about 4 minutes – then add eggs one at a time, scraping the bowl between additions.150 g unsalted butter, 185 g brown sugar, 2 large eggs
- Add the bananas, sourdough discard, and extracts mixing until combined.200 g sourdough discard, 1 teaspoon vanilla extract, 1 teaspoon bourbon extract
- Finally, add the dries in two separate stages, mixing gently before finally folding in the walnuts.150 g chopped walnuts
- Bake for about 60-65 minutes or until you’ve checked for doneness with a toothpick and it comes out clean. Remove from the oven and allow to cool in the pan for 25 minutes before carefully transferring to a wire rack to cool completely.
- What is sourdough discard? As you continue to feed a sourdough starter with fresh flour and water, some of the starter must be thrown away or else it’ll become overly acidic and too big and unmanageable. The starter you throw away is known as the discard.
- Help! I don’t have any ripe bananas. What should I do? You can quicken the ripening process by placing the bananas in a brown paper bag for a few days.
- Can you make banana bread with frozen bananas? You can, but it’s best to let them thaw first. They’ll be easier to mash and work with this way.
- How do you store sourdough banana bread? Place the cooled loaf or slices of banana bread in an airtight container. Store at room temperature for 3 or 4 days, or in the fridge for up to 1 week.
- Is it freezer-friendly? Yes, banana bread freezes very well. Wrap the loaf or individual slices in plastic or aluminum foil and freeze for up to 3 months.