Sourdough Discard Strawberry Crumb Bars
Last Updated on June 24, 2026 by Jamie Saechao
Jump to RecipeBursting with seasonal strawberries and sourdough tang, these easy sourdough strawberry crumb bars are the perfect summer treat!
Sourdough strawberry crumb bars combine old fashioned rolled oats with sweet jam to give you a thick and chewy bar that is perfect for picnics, bar b que’s and pool days!
Hey friends, I just want to let you know that this recipe is 100% human-created. The recipe was created, photographed and written by me.
For more sourdough summer recipes try sourdough blueberry muffins, sourdough lemon blueberry muffins, sourdough zucchini bread and sourdough zucchini muffins.
Why You’ll Love Them
- This one bowl recipe is very quick and easy to make – the perfect recipe for summer picnics and parties
- Made with simple pantry ingredients like rolled oats, jam, and brown sugar.
- These bars can be frozen and saved for special summer occasions.
- This treat is a great way to use up extra sourdough discard (just like my oatmeal raisin sourdough cookies or sourdough granola!).
Ingredients
This recipe uses just a few pantry staples:
- All purpose flour: use a kitchen scale to weigh the flour for best results
- Rolled oats: use old fashioned rolled oats, not quick oats
- Brown sugar for a little sweetness
- Lemon zest: optional, but adds tartness
- Baking soda
- Salt: Enhances all the flavors
- Vanilla
- Cinnamon: A pinch of cinnamon adds warm flavor to these sourdough bars
- Sourdough discard: I like to use fresh discard, but you can use whatever you have on hand. Older discard will be more sour! Cold or room temperature starter works.
- Strawberry jam or preserves
- Fresh strawberries, thinly sliced
- Butter: firm room temperature butter, cut into chunks
Craving more bars? Try these sourdough brownies.
What Is Sourdough Discard?
Sourdough discard is the un-used portion of your sourdough starter that is often thrown away. Since it is simply fermented flour and water, it can be added to baked goods for added flavor, tang and even digestibility!
Learn how to make a sourdough starter here.
How To Make Sourdough Discard Strawberry Crumb Bars
Preheat oven to 350 degrees F and line a 9-inch square baking pan with parchment paper. Leave a few inches of overhang on opposites of the pan for easy removal.
Cut the butter into 12-14 chunks, about a tablespoon each.
Make the dough: In a stand mixer fitted with paddle attachment (or use a bowl and handheld mixer), combine flour, oats, brown sugar, baking powder, lemon zest, cinnamon, and salt on medium speed. Add in the vanilla and sourdough discard and beat until combined.
With the mixer on low, add in the chunks of butter one at a time. Mix until the butter has broken down into pea sized shapes. The dough should be crumbly.
Bake the crust: Press two-thirds of the mixture into the prepared pan and use the bottom of a glass cup or measuring cup to pack the crust down tightly. Bake for 10 minutes.
Remove the crust from the oven and add the warm jam to the crust, smoothing it with a spatula. Spread the strawberries in a thin layer over the top of the jam.
Add the topping: Sprinkle the remaining crumb mixture over the top of the strawberries and lightly press down. Bake for 45-50 minutes or until the top is golden brown.
Let the bars cool completely, then remove them with the edges of the parchment paper and cut into 16 pieces.
Storage
Store for 1-2 days in an airtight container or up to 5 days in the refrigerator. To freeze, wrap with plastic wrap, then aluminum foil and freeze for up to 3 months. Thaw overnight in the refrigerator.
Long Ferment Option
Place the dough in the refrigerator for 2-24 hours for a longer ferment option.
Tips On Sourdough Discard Crumble Bars
- Make sure to let the bars cool completely before cutting, or they may fall apart
- Use a kitchen scale for more accurate flour measurements
- Firm room temperature butter will give you the best results for your jam bars
- If you only have active starter you can stir it down and use in place of discard
For more summer recipes try these sourdough hamburger buns, 4th of July fruit salad, or kid’s fruit salad.
Sourdough Discard Strawberry Crumb Bars
Equipment
- Stand mixer or handheld mixer
- Mixing bowls
Ingredients
- 2 cups all purpose flour 240 grams
- 1.5 cups rolled oats 130 grams
- 3/4 cup brown sugar 150 grams
- 1 tsp baking powder
- 1 tsp lemon zest optional
- 1/2 tsp ground cinnamon
- 1/2 tsp salt
- 1.5 tsp vanilla extract
- 1/2 cup sourdough discard 100 grams
- 1 3/4 sticks unsalted butter, cut into 12 chunks (room temperature) 14 tablespoons
- 1 cup strawberry jam
- 1 cup thinly sliced strawberries
Instructions
- Preheat the oven to 350 degrees F and line a 9-inch square baking pan with parchment paper. Leave a few inches of overhang on opposites of the pan for easy removal. Cut the butter into 12-14 pieces, about a tablespoon for each piece.
- In a mixing bowl fitted with paddle attachment, mix the flour, oats, brown sugar, baking powder, lemon zest, cinnamon, and salt on medium speed. Add in the vanilla and sourdough discard and beat until combined. *You can mix with a handheld mixer if needed.
- With the mixer on low, add in the chunks of butter one at a time. Mix until the butter has broken down into pea sized shapes. The batter should be crumbly.
- Press two-thirds of the mixture into the prepared pan and use the bottom of a glass cup or measuring cup to pack the crust down tightly. Bake for 10 minutes.
- Spread the jam evenly into the baked crust, then arrange the sliced strawberries over the jam. Sprinkle the remaining crumb mixture over the top and press it down lightly.
- Bake for 45-50 minutes. The crust should be golden brown and the jam bubbling around edges. Cool the bars completely before removing from the pan.
- When cool, lift the bars up by the edges of the parchment paper and cut into squares.
Notes
- Make sure to let the bars cool completely before slicing.
- Firm room temperature butter will give you the best results for your jam bars.
- If you only have active starter you can stir it down and use in place of discard.
- If you don’t have any sourdough discard or starter you can simply leave it out of the recipe!
