Sourdough Brookies (Brownie + Chocolate Chip Cookie Bars)
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Sourdough discard brownies plus sourdough chocolate chip cookies equals this magical combination known as “brookies”. Brookies are easy to make and yield sourdough cookie bars that are chewy, fudgy, and utterly irresistible!
The Ultimate Combo Sourdough Cookie Bar
These sourdough brookies are a mashup of two classic desserts — fudgy sourdough brownies and sourdough chocolate chip cookie bars. Arguably, the two most popular treats on the planet all swirled together in one spectacular pan.
There are a few extra dishes involved with this recipe because you have to prepare the brownie batter and the cookie batter separately, but each mixture is super easy to make, and there is no mixer required, zero chilling time, and just one 8×8 baking pan.
Sourdough discard desserts like this one are a perfect way to use up excess starter and enhance the flavor of your favorite treats like cookies, brownies, and muffins. For more classic sourdough cookie recipes, try these reader-favorite sourdough oatmeal cookies or these traditional sourdough chocolate chip cookies.
Recipe Box Repertorire
Reasons why this recipe is worth adding to your recipe collection.
- These sourdough discard cookie bars use simple pantry ingredients, meaning you can probably make them right now!
- If you’re looking for 8×8 cookie bars, you really can’t beat these.
- You can make it ahead of time, swirl the batters in the pan, cover, and refrigerate for up to 3 days. Then, you’ll have a show-stopping sourdough discard dessert ready to go whenever you want it!
How-To Make Brookies + Photos
- Line your 8×8 inch baking pan with parchment paper so that it is overhanging on two sides.
Make the cookie batter.
In a medium mixing bowl, make the batter for the sourdough discard chocolate chip cookies. Mix cooled melted butter, sugars, discard, egg, and vanilla.
Add the spooned and leveled flour, cornstarch, baking powder, and salt, mix, then fold in the chocolate chips.
Make the brownie batter.
Melt the butter in a saucepan and whisk in the chocolate chips and cocoa powder. Add the smooth chocolate mixture to another bowl, then stir in the sugars and discard.
Sprinkle the flour over the top, mix, and fold in the mini chocolate chips.
Once the cookie batter and brownie batter are ready, scoop them into the baking pan.
Using a cookie scoop or spoon, alternate dolloping the two batters into the pan. Try to keep them evenly dispersed and then swirl the batters together with a butter knife.
Bake in a preheated oven until the brookies pass the toothpick test, then allow them to cool before removing and slicing.
Key Tips
1. Line your baking pan with parchment paper so that it overhangs a bit on two sides. This way, you can easily remove the brookies from the pan.
2. When making the cookie batter, allow the melted butter to cool a bit before adding in your sugar to prevent it from melting the sugars.
3. It’s better to pull the brookies out too soon rather than too late. You don’t want to overcook them, so use a toothpick to test for doneness. Insert it into the center, and it should come out clean or with some sticky crumbs. If you think you hit a chocolate chip, try again in another spot.
FAQ & Variations
You want the brookies to be moist and fudgy, so it’s important to pull them out before they get over-baked. Check with a toothpick at the 30-minute mark. Insert it into the center and pull it out. It should come out clean or, better yet, with a few moist crumbs. The toothpick shouldn’t come out covered in wet batter.
Yes, you can make both batters, swirl them in the pan, and then store them covered in the fridge for up to 3 days. Bake them straight from the refrigerator. They may need a couple of extra minutes of baking time.
These brookies should be moist and fudgy like a sourdough brownie. If the bars turn out dry and crumbly, reduce the bake time the next time you give them a go.
Yes! If you are a nut lover, try adding in a half cup of chopped walnuts or pecans right before swirling the batters.
Another fun variation is to sprinkle a handful of regular or mini M&Ms over the top of the batter before baking. Or try mini marshmallows!
How To Store and Freeze Brookies
Brookies will keep well for up to 1 week at room temperature, covered in an airtight container.
They can also be frozen. Allow them to cool completely, then store them in a freezer-safe container or bag for up to three months.
If you’ve tried this Sourdough Brookies Recipe, remember to rate the recipe and let me know how you got on in the comments below. I love hearing from you, and it helps me so much! — Thank you.
More favorite recipes from Rooted Deep Home:
Sourdough Brookies (Brownie + Chocolate Chip Cookie Bars)
Equipment
- 8×8 baking dish I use this heavy-duty USA square baking pan
- Mixing bowls
Ingredients
Chocolate Chip Cookie Dough
- 1/2 cup unsalted butter melted and slightly cooled
- 1/3 cup packed brown sugar light or dark
- 3 tablespoons granulated sugar
- 1/4 cup sourdough starter discard or fed
- 1 egg room temperature
- 1/2 teaspoon vanilla extract
- 1 cup all-purpose flour
- 1 teaspoon cornstarch
- 1 teaspoon baking powder
- 1/2 teaspoon salt
- 1/2 cup semisweet chocolate chips
Brownie Batter
- 1/2 cup unsalted butter
- 1/4 cup semisweet chocolate chips
- 1/4 cup cocoa powder
- 1/2 cup packed brown sugar light or dark
- 1/4 cup granulated sugar
- 1/4 cup sourdough starter discard or fed
- 2 eggs room temperature
- 1/2 teaspoon vanilla extract
- 1/4 teaspoon salt
- 1/2 cup all-purpose flour
- 1/4 cup mini chocolate chips optional
Instructions
- Start by getting the eggs to room temperature (you can do this quickly by covering them with warm water for 5 minutes). Melt the butter for the cookie dough (1/2 cup unsalted butter) and allow it to begin cooling.
- Preheat the oven to 350F (175C) and line an 8×8 inch baking dish with parchment paper, or use baking spray to grease it. Set aside.
Cookie Dough
- Combine the melted, cooled butter with the sugars in a medium mixing bowl and stir well. Add the sourdough starter, egg, and vanilla, and mix again.
- Sprinkle the flour, cornstarch, baking powder, and salt over the cookie dough batter and stir until just combined. Then fold in the chocolate chips. Set aside.
Brownie Batter
- Combine the butter, chocolate chips, and cocoa powder in a saucepan over medium-low heat, stirring frequently until smooth and completely melted. You can also use a microwave heating in 20-second intervals.
- To another medium mixing bowl, add the melted chocolate mixture and the sugars and mix well. Add in the sourdough starter, eggs, vanilla, and salt.
- Sprinkle the flour over the batter and stir until combined. Then fold in the mini chocolate chips if using.
Assembly
- In an alternating pattern dollop large spoonfuls of cookie dough and brownie batter into the baking dish. A cookie scoop works well for this. Use a butter knife to swirl both doughs together, keeping the batter in an evenly dispersed layer.
- Bake in a 350F (175C) oven for 30-35 minutes or until a toothpick inserted in the center comes out with a few moist crumbs (make sure you're not sticking the toothpick into a chocolate chip!). Overbaked brookies will be dry and crumbly, so check them at the 30-minute mark.
- Let the brookies cool completely in the pan before removing and slicing. Enjoy!
