Sourdough Pumpkin Brownie (with brown butter)

Brownies are quite possibly my single favorite dessert. It’s hard to imagine making that classic dessert any better, but this Sourdough Pumpkin Brownie (with brown butter) just might take the cake. Or the brownie? Sorry, I had to. They’re the kind of treat that makes your kitchen smell like brown butter and cinnamon, and they look so fun and festive that no one will believe how simple they are to make.

The sourdough discard keeps them soft and chewy for days, the brown butter adds a warm nutty depth, and those pumpkin blondie swirls turn every slice into its own tiny pumpkin patch. Perfect for Halloween, Thanksgiving, or whenever you’re craving a little cozy chocolate pumpkin magic.

Why You’ll Love This Recipe:

This recipe uses brown butter that truly elevates the flavor to something that leaves you asking WHAT WAS THAT? No need for special ingredients like baker’s chocolate, just melt chocolate chips with cocoa for the perfect brownie base.

Add in a layer of pumpkin blondie with a touch of pumpkin spice that perfectly balances the chocolate, swirled to create the cutest little pumpkins which will be such a hit at all your fall parties. Simple to make with bakery worthy results! Top with flaky sea salt for maximum flavor.

*As an amazon affiliate this post may contain affiliate links, which means I may receive a commission for qualifying purchases. I will only recommend products that I personally love and use.*

Tools You’ll Need:

9×9-inch baking pan- to bake your brownies. I love this pan from USA Bakeware linked here.
Parchment paper- to line your brownie pan for easy removal.
Medium saucepan or pot- to brown the butter.
Mixing bowls- to mix the brownie and blondie batter.
Whisk- to mix the batter.
Spatula- to spread the brownie and blondie batter.
Toothpick or skewer- to swirl the batter to shape the pumpkins.
Piping bag or Ziplock bag (optional)- to pipe green stems.

Sourdough Pumpkin Brownies (with brown butter)

Next, Gather Your Ingredients:

Sourdough discard– Adds flavor and moisture and is the magic that ferments your brownie and blondie batter. Can be used fed, past peak, or straight from the fridge.
Pumpkin Puree- Adds that classic pumpkin flavor to the blondie portion of the brownie. Do not use pumpkin pie filling, this isn’t the same as pumpkin puree. I like to use Libby’s I find it has less water which helps the brownie be less cakey.
Semi-sweet chocolate chips- melted into the brown butter for a deep, glossy chocolate base.
Dutch-process cocoa powder – smooth, dark flavor for that classic brownie intensity. If you don’t have Dutch-process you can substitute for any cocoa powder. I prefer a darker variety.
All-purpose flour – Provides structure to the brownies.
Cinnamon, Ginger Nutmeg, and Cardamom – The perfect spices to blend into the pumpkin blondie to add that “pumpkin spice” taste.
Unsalted Butter – Browned to golden perfection to really elevate the flavors in the brownie.
White Granulated Sugar- Sweetens the brownie and blondie and gives that chewy texture and crackly top.
Brown Sugar- adds molasses flavor and chewiness.
Eggs – Helps the brownie bind and rise.
Vanilla extract – Adds warm cozy flavor.
Sea Salt – Enhances overall flavor.
Espresso powder- a touch enhances the chocolate flavor (not coffee-like). I love this espresso powder from King Arthur linked here.
Maldon Sea Salt (optional)- adds an extra touch I love to accentuate the chocolate. You can find it linked here.
Orange and Green Food Coloring (optional)- to enhance the color of the pumpkin and to color the green stems. This is completely optional but I love the added touch!

Instructions

Step 1: Brown the Butter

In a medium sized pot, melt all your butter for the brownie and blondie (3/4 cup or 170g) over medium heat. Allow to gently cook, whisking occasionally until the butter is a deep golden brown with small amber flecks.

Remove from heat immediately and measure out out 1/4 cup or 50 g of the browned butter into a separate bowl for the blondie.

Brown butter for the blondie and brownie base

Step 2: Mix the Brownie Base

Return the pot with the 1/2 cup (115g) of browned butter to the stove and on low heat, add the chocolate chips, cocoa powder, and espresso powder to the pot. Whisk on low heat until the chocolate has just fully melted and all of the ingredients are fully incorporated.

Add chocolate chips, cocoa, and espresso powder to butter

Whisk until smooth — Add chocolate chips, cocoa, and espresso powder to butter

Transfer from heat as soon as the chocolate has melted, then pour into a bowl to finish the brownies. Whisk in granulated sugar, brown sugar, sourdough discard, eggs and vanilla.

Whisk the brownie batter until shiny and cohesive.

Fold in flour and salt just until no streaks remain, try not to overmix at this point you just want the flour incorporated.

Whisk until smooth and glossy — Add remaining wet ingredients

Set aside the brownie batter while you mix your pumpkin blondie base.

Step 3: Mix the Pumpkin Blondie Batter

In the bowl you set aside with the 1/4 cup browned butter, add the brown and white sugar. Whisk to combine.

Add egg yolk, sourdough discard, vanilla, and pumpkin purée to the bowl, and whisk until combined.

Add in your flour, salt, cinnamon, nutmeg, ginger, and cardamom. Mix until just combined and no streaks remain; avoid overmixing at this point or the blondie will be cakey.

Set aside 1/8 cup of batter, and add a little green food coloring to make the pumpkin stems. Stir it really well, and transfer to a piping or ziplock bag. Set aside for later.

If you want a more orange color to the pumpkin layer, add a little bit of orange food coloring to the pumpkin blondie and mix it really well to incorporate the food color. Set aside.

Overnight Fermentation Option: If you want to ferment this brownie and blondie batter, cover with plastic and refrigerate overnight. When you’re ready to bake your brownie, allow to rest at room temperature for about an hour to warm up. Stir with a spatula after batter has come to room temperature, and proceed with baking. You can do this with the pastry bag as well with green batter, just allow to warm up and use your hands to gently squeeze and warm before you pipe.

Step 4: Assemble the Brownies

Preheat your oven to 350 °F (175 °C) . Line a 9×9 metal pan with parchment paper, then lightly spray with cooking oil.

Spread half the brownie batter at the bottom of the pan, making sure its spread to the edges of the pan.

Spread 2/3 of the pumpkin blondie batter to the center, spreading a thin layer of the blondie batter on top of the brownie batter.

Layer the rest of the brownie batter on top of the blondie, spreading the brownie batter to the edges.

Add the pumpkin blondie center — Add a layer of brownie batter

Drop small spoonfuls of the remaining pumpkin blondie on top of the brownie, spreading to form little ovals.

Using a toothpick or skewer, draw lines up through the pumpkins to create little brown lines giving definition to the pumpkin.

Grab the bag with the green batter, and cut a very small piece off of the tip.

Pipe little green stems and vines on the pumpkins.

Step 5: Bake the Brownies

Bake at 350 °F (175 °C) for 40 minutes, or until a toothpick inserted in the center comes out with moist crumbs.

Cool completely in the pan before slicing. Cover with plastic and refrigerate to allow the brownie to setup if you want it extra firm.

Top brownie with flaky sea salt for extra flavor (you don’t have to but it’s so delicious).

Cut brownie into 9 even sections and enjoy!

Yields 9 brownies

How to Store:

Room Temperature- Store in an airtight container up to 3 days.

Refrigerator- Keeps up to 5 days in an airtight container. Gently warm before serving.

Freezer- Wrap individual slices in plastic and freeze up to 2 months; thaw and warm before serving.

FAQ’S:

Do I have to brown the butter?

No, but it’s worth it! Brown butter gives the brownies a nutty, caramel-like depth that elevates them from good to unforgettable. If you want to skip this just use melted butter instead with equal measurements.

Can I double the recipe?

Absolutely. Double all ingredients and bake in a 9×13-inch pan for 40–45 minutes.

How do I get clean cuts?

Chill the brownies for at least 1 hour before slicing. Use a sharp knife and wipe it clean between each cut for bakery-perfect edges.

Can I use pre-mixed pumpkin spice powder?

Yes! Use 1 teaspoon cinnamon and 1 teaspoon pumpkin pie spice instead.

Can I use pumpkin pie filling?

No. Pumpkin puree is what you want to use, pumpkin pie filling has sugar and other ingredients added that will change the brownies.

If you enjoyed this recipe, drop a comment and don’t forget to try my other seasonal pumpkin recipes!

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