Easy Sourdough Discard Blueberry Buckle Recipe
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Late spring and early summer are blueberry season, when fresh berries start appearing on the counter, and favorite recipes like blueberry pancakes, muffins, coffee cakes, and cobblers return to the table. One recipe my Michiganian dad still asks for every year is my grandma’s Blueberry Buckle. Each spring, I pull out her checkered recipe card and bake it with a small update: sourdough starter, which adds a gentle tang and makes the crumb softer and more tender. Fresh blueberries, a little lemon zest, and a crunchy streusel topping make this buckle perfect for breakfast, afternoon tea, or a simple dessert.
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Why You’ll Love This Recipe:
- Quick and Easy-This recipe is simple to make and comes together quickly, so it’s perfect when you want something tasty without a lot of effort. You can even prepare the crumble ahead of time and freeze it in a zip-top bag, which saves you even more time later. The Pumpkin Coffee Cake is another single-pan treat that’s easy to make. It too has a tender crumb with a crunchy topping.
- No Waste-If you have leftover sourdough starter, this buckle is a smart way to use it. The starter adds flavor and keeps the cake soft and moist. You can also try Sourdough Coffee Cake with Buttery Cinnamon Streusel, another recipe that turns starter into a rich, buttery cake.
- Use Up Extra Blueberries-During blueberry season, you probably have plenty of berries on hand. This buckle is a slightly different way to enjoy them, adding variety to your usual sourdough muffins or cobblers and giving you another recipe to rotate into your baking routine. This Mixed Berry Cobbler is another fruit-focused dessert that makes good use of extra berries.
Ingredients & Substitutions
* To find precise measurements, scroll to the bottom of this post to find the recipe card*
- All-purpose flour – My favorite brand to use is King Arthur’s Flour
- Baking powder – Helps the cake rise for a light, tender crumb
- Salt – Any unrefined salt will do, but my favorite is Redmond’s unrefined salt for some extra minerals!
- Butter – Softened; adds richness and moisture to the cake
- Sugar – Granulated white sugar; sweetens the batter and helps the crumb brown lightly
- Sourdough Starter – I find sourdough discard that is about 24–48 hours old works best for this recipe; however, you can use even older discard for a more tangy taste
- Milk – Helps combine the ingredients and keeps the cake soft
- Egg – Binds the batter and adds structure
- Vanilla Extract – Adds subtle flavor to complement the blueberries and lemon zest
- Lemon zest – Only peel the very outside of the lemon rind. If you zest too deeply, the white part tends to be very bitter
- Blueberries – Fresh is best, but you can use frozen and make this treat any time of the year; they add natural sweetness and moisture to the cake
Crumble Topping
- White Sugar – Sweetens the topping for a lightly crisp finish
- Brown Sugar – Adds sweetness and a hint of molasses flavor
- Flour – Helps create the crumbly texture
- Cinnamon – Adds a warm spice note that complements the blueberries
- Butter – Be sure to use cold butter. Room-temperature or melted butter will cause the topping to spread out and flatten when it bakes
How to Make Sourdough Blueberry Buckle
- In a medium bowl, add white and brown sugar, flour, cinnamon, and cold, cubed butter.
- Crumble the larger pieces of butter with your fingers and mix by hand until the butter is well coated with the flour mixture.
- Work quickly to prevent the butter from getting too soft. Softened butter will melt during baking and result in a flat crust rather than a crunchy crumble.
- Place the bowl of crumble topping in the fridge to chill until ready to top your sourdough blueberry buckle.
- Preheat your oven to 375°F. Then, grease the inside of a round cake pan or 9×9 square pan with butter or cooking spray.
- In a large bowl, whisk together 1 1/2 cups flour, 2 1/2 teaspoons baking powder, and 1/2 teaspoon salt. Set aside.
- In the bowl of an electric mixer with the paddle attachment, cream 3/4 cup sugar and 1/2 stick of softened butter until light and fluffy. Add a large egg and mix until the batter turns pale yellow.
- In a medium bowl, mix together 1/2 cup sourdough starter, 1/2 cup milk, 1 tablespoon lemon zest, and 1/2 teaspoon pure vanilla extract.
- Add the wet ingredients to the mixer and mix on low speed for about a minute, stopping occasionally to scrape the bottom and sides of the bowl so everything is incorporated.
- Add the dry ingredients to the wet ingredients, half a cup at a time, mixing on low speed. Be careful not to over-mix the batter.
- In a large bowl, pour flour over the fresh or frozen blueberries—just enough to coat them, about a couple of tablespoons.
- Mix with a wooden spoon until evenly coated.
- Scoop half of the batter into the prepared pan and spread it smoothly.
- Pour 1 cup of blueberries on top of the batter. Place the remaining batter on top and spread evenly.
- Then add the remaining blueberries.
- Sprinkle an even layer of the crumble topping over the cake, making sure to cover the edges. Place the pan in the preheated oven and bake for 45–50 minutes, until golden brown. Test with a toothpick in the center; if it comes out clean, the buckle is done.
- Remove the buckle from the oven and let it cool on a wire rack. Once it’s just warm to the touch, slice into wedges or squares and display on your favorite serving plate. Whether you call it a buckle, coffee cake, or sourdough blueberry crumb cake, it’s perfect with a steaming cup of coffee or tea. You can serve it warm or at room temperature, and an extra scoop of vanilla ice cream, custard, or homemade whipped cream is always welcome. Good luck saving any for the next day-they are that scrumptious.
McKenna’s Helpful Tips
- Prepare the crumble ahead of time – You can make the crumble topping in advance and chill it in the fridge or freeze it in a zip-top bag. This saves time when you’re ready to assemble the buckle and helps keep the topping crisp.
- Use 24–48-hour sourdough discard – Sourdough discard that’s 24-48 hours old adds a gentle tang and keeps the buckle soft and tender. Using discard that’s younger or older can affect the flavor or texture, so sticking to this range helps your cake stay moist and balanced.
- Coat blueberries in flour – Before folding fresh or frozen blueberries into the batter, toss them in a little flour. This prevents them from sinking to the bottom, ensuring even distribution throughout the cake.
- Check doneness with a toothpick – Bake until golden and test with a toothpick in the center. If it comes out clean, the buckle is done. This ensures the cake is fully baked while keeping it soft and tender inside.
How to Store
If you have leftover buckle, wrap it tightly in plastic wrap or put it in an airtight container. It will keep at room temperature for 2–3 days. For longer storage, slice and freeze the pieces in a freezer-safe bag or container. Thaw slices on the counter, and you can warm them a little in the microwave or oven before serving if you like.
FAQs
What is a Buckle?
A buckle is a coffee-cake-style dessert with a sweet crumble topping and a fruit-filled base. Some people call it “boy bait” because it is so irresistible. As the cake rises, the weight of the blueberries causes it to buckle or crack around the fruit.
Can I Make a Sourdough Blueberry Buckle with Different Fruits?
Blueberries are the family favorite, but you can swap in strawberries, blackberries, rhubarb, or cherries. You can also skip the lemon zest and add extra cinnamon if you like.
Can I Use Frozen Blueberries?
Yes. Frozen blueberries make this cake a year-round treat. Coat them lightly with flour to help them stick to the batter and keep them from sinking to the bottom while baking.
Sourdough Blueberry Buckle Recipe
Yield: 16 slices
A sweet and tender cake, sprinkled with a crunchy streusel topping and speckled with fresh blueberries, this Sourdough Blueberry Buckle is quick to make and sure to impress. Perfect to serve as breakfast, with afternoon tea, or after-dinner dessert. Make with fresh blueberries during the blueberry season or with frozen blueberries to enjoy all year long.
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Ingredients
Crumble Topping
- 50 grams sugar 1/4 cup
- 55 grams brown sugar 1/4 cup
- 47 grams all-purpose flour 1/3 cup
- 1 gram cinnamon 1/2 teaspoon
- pinch of salt
- 57 grams unsalted butter, cold 1/4 cup
Sourdough Blueberry Buckle
- 210 grams all-purpose flour 1 1/2 cups
- 8 grams baking powder 2 teaspoons
- 3 grams salt 1/2 teaspoon
- 150 grams sugar 3/4 cup
- 57 grams unsalted butter, softened 1/4 cup
- 1 large egg room temperature
- 140 grams sourdough discard heaping 1/2 cup
- 155 grams milk 1/2 cup + 2 Tablespoons
- 3 grams fresh lemon zest 1 Tablespoon
- 4 grams pure vanilla extract 1 teaspoon
- 300 grams fresh or frozen blueberries 2 cups
- 10 grams all-purpose flour, for blueberries 1 Tablespoon
Instructions
Crumble Topping:
- In a medium bowl, add the sugars, flour, cinnamon, pinch of salt, and the cold, cubed butter.50 grams sugar, 55 grams brown sugar, 47 grams all-purpose flour, 1 gram cinnamon, pinch of salt, 57 grams unsalted butter, cold
- Crumble the larger pieces of butter with your fingers and mix by hand until the butter is well coated with the flour mixture.
- Place in the fridge to chill until ready to top the sourdough blueberry buckle.
Sourdough Blueberry Buckle
- Preheat your oven to 375 degrees F. Grease a round 9-inch cake pan or 9×9 square pan with butter or cooking spray. Set aside.
- In a large bowl, whisk together the flour, baking powder, and a salt until incorporated. Set aside.210 grams all-purpose flour, 8 grams baking powder, 3 grams salt
- In the bowl of an electric mixer with the paddle attachment, cream the sugar and softened butter until it is light and fluffy.150 grams sugar, 57 grams unsalted butter, softened
- Then add a large egg and mix until pale yellow color.1 large egg
- In a medium bowl, whisk the sourdough starter, milk, lemon zest and vanilla extract until smooth.140 grams sourdough discard, 155 grams milk, 3 grams fresh lemon zest, 4 grams pure vanilla extract
- Add the wet ingredients to the stand mixer and mix on low speed for about a minute, stopping to occasionally scrape the bottom and the sides of the bowl.
- Add the dry ingredients to the wet ingredients, half a cup at a time while mixing on low speed. Be sure not to over-mix the batter. Stop mixing once the flour is just incorporated.
- In a large bowl, pour the remaining flour over the fresh or frozen blueberries. Mix with a wooden spoon until the blueberries are evenly coated with flour.300 grams fresh or frozen blueberries, 10 grams all-purpose flour, for blueberries
- Scoop half of the batter into the prepared pan and spread smoothly with an offset spatula. Pour half of the blueberries on top of the batter. Place the remaining batter on top and spread evenly. Add the remaining blueberries on top of the cake.
- The finishing touch is to sprinkle an even layer of the crumb topping – don't miss the corners!
- Place your pan into the preheated oven and bake until the 45-50 minute mark or until golden brown and a toothpick placed in the center comes out clean.
- Remove the sourdough blueberry buckle from the baking dish and cool on a wire rack.
- Once it is just warm to the touch, slice it up in wedges or squares and display them on your favorite serving plate. Enjoy!
Notes
This recipe card was updated on February 15th, 2026.
Recipe Tips
-
- Cover the sourdough blueberry buckle with plastic wrap once completely cooled or store it in an air-tight container. It will keep for 2-3 days.
- No need to thaw your frozen blueberries before folding them into the batter. If you do, the blueberry juices may turn the batter purple. A fun presentation, but not a traditional, serving style. Flour and add just like fresh.
- This buckle recipe can be made with an array of different fruits. Swap blueberries out for strawberries, blackberries, rhubarb, or even cherries!
- To freeze, cover the buckle with a layer of plastic wrap, then a layer of aluminum foil once it is completely cooled, and store it in a plastic gallon-sized bag. It will keep for up to 3 months. Thaw on the countertop before serving.
Nutrition
Calories: 203kcal | Carbohydrates: 34g | Protein: 3g | Fat: 7g | Saturated Fat: 4g | Polyunsaturated Fat: 0.4g | Monounsaturated Fat: 2g | Trans Fat: 0.2g | Cholesterol: 27mg | Sodium: 158mg | Potassium: 58mg | Fiber: 1g | Sugar: 18g | Vitamin A: 219IU | Vitamin C: 2mg | Calcium: 52mg | Iron: 1mg
Tried this recipe?Please leave a comment on the blog or share a photo on Instagram!
Wondering if this could be put together at night and put in the refrigerator to bake the following morning?
Hi:) do you use salted or unsalted butter?
Unsalted butter! But if all you have is salted, just omit 1/4 tsp of salt from the recipe.
Can I ferment the batter in the fridge overnight, or is it better to make this right before baking?
You can absolutely do a long ferment in the fridge!
I followed the recipe except used 1 1/2 tsp lemon oil instead of the lemon zest. Mixed it up and put it right into the oven.
I tried an experiment using half low carb flour ( a mix of almond, oat fiber, coconut and vital wheat gluten) and the other half was all purpose flour. Used monk fruit white and brown sugars and left everything else the same and it came out fabulous! Great recipe thank you!
Thank you for sharing this variation! So glad you enjoyed it 🙂
Absolutely delicious! My 2yo and 7yo ate 1/4 of this as soon as I pulled out of oven!
Love this! Thank you so much for sharing!
Made this for a dinner (dessert) at church! Was a huge hit! Question-Can the recipe be doubled?
So happy to hear it was enjoyed by all! Absolutely! If you double it, I would bake it in 2 separate cake pans.
This was SO good!! I’ll make this regularly. Thank you for the recipe!
How do you think this would bake up in a loaf pan? I’m thinking a one pound one.
Thanks again!
I’m so glad you enjoyed it! I grew up eating it, so this recipe is dear to my heart. I wouldn’t see why it wouldn’t work! Thank you for sharing!
Should this be with bread or all-purpose flour? The recipe say AP, but your post says you like to use “Bread” flour.
Apologies for the confusion – I meant to say “King Arthur’s Flour”. The recipe should be made with all-purpose flour. Thanks!
I’ve made the Blueberry Buckle cake 4 times and each time I’ve baked it, it has turned out excellent!!! A new family favourite and you are correct, no need to worry about left overs as it’s usually gone the same day. Thank you for creating a wonderful recipe that I can use my discard with!!!
Thank you so much for sharing, Trudi! This recipe is near and dear to my heart, so it brings my such joy hearing that it is loved in your kitchen as well 🙂
I made this tonight and couldn’t wait to leave a comment. So, so good! Simple ingredients. It baked up perfectly. I can hardly wait until tomorrow morning when I can have another piece. Thanks for this great recipe!
Yay!! So happy to hear you all enjoyed it. Thank you for sharing!
I made this in a 9 inch glass deep dish pie pan and it turned out wonderfully. Great recipe! Served with whipped cream while warm.
Sounds lovely! Thank you for sharing.
I used fresh picked Idaho huckleberries! It was delicious! Thank you for this wonderful recipe. It’s going to be saved.!
Sounds delicious! Thank you for sharing.
Yum and so easy to make!
Thank you for sharing! So glad you enjoyed this recipe.
I turned this recipe into muffins. My husband liked it better than a regular muffin recipe!
Love this idea!
I’ve made this recipe several times and it’s always good. I have a question about the amount of flour in grams. If 1 cup of flour is 120 grams, then 1 1/2 cups should be 180 grams, not 210.
Hi Kimberly! Thank you for your detailed observation! You’re absolutely right, flour measurements can vary depending on how it’s scooped. For this recipe, I weighed the flour at 210g, which I personally found to be about 1 1/2 cups when using my usual scoop and level method. I understand how this may vary, especially since standard conversions can place 1 cup closer to 120-125g, rather than the 140g I referenced.
Baking by weight is certainly the best way to ensure consistency, so I recommend sticking to the 210g for the most accurate results. Happy baking, and I hope you continue to enjoy this recipe!
Hello!
I love this recipe and I make it all the time!
I was wondering if I would be able to use a Bundt cake pan for this recipe, would I need to double the recipe?
So glad you love the recipe, Hal —thank you for making it often! For a Bundt cake pan, which is much larger, I would recommend doubling the recipe to ensure it fills the pan nicely. Just keep an eye on the baking time, as it may take longer to bake all the way through. I hope that helps, and I’d love to hear how it turns out!
Hello,
I am wanting to make this for a brunch I’ll be attending this week. I am considering making this in a 9×13 dish.
Should I double the recipe, or would that not be enough? Also, what would you recommend for baking time if using a 9×13?
Thank you!
A 9×13 pan is quite a bit larger than the 9-inch pan the recipe is written for, so I do recommend doubling the recipe. A single batch would bake up very thin and more like a bar than a buckle.
When doubling and using a 9×13 pan, I’d suggest baking at the same temperature and starting to check for doneness around 45–50 minutes, with a total bake time closer to 55–65 minutes. You’re looking for a set center, lightly golden edges, and a crumb topping that’s nicely baked. I hope it’s a hit at brunch—let me know how it goes!
Very good! My new favorite way to use unclaimed discard and need to use now blueberries. A big hit with whole fam. I feared a whole tablespoon of lemon zest would be too much but it was just right to brighten the flavor
This makes me so happy to hear — thank you for sharing! So glad it was a hit with your whole family!