Pumpkin Swirl Brownies

Give your brownies a fall twist with these Pumpkin Swirl Brownies! Easy, mix-by-hand chocolatey brownies mixed with pumpkin batter for a customizable chocolate and pumpkin treat! Which one will you grab: more chocolate or more pumpkin?

pumpkin swirl brownies on a white background lined up in a square.

Is it really even fall if a food blogger doesn’t share a new pumpkin recipe?  No, no it is not, so today I will fulfill my contractual duty.

I love pumpkin, but I live with a bunch of chocolate lovers.  How better to meld the two than with some pumpkin swirl brownies?

For these pumpkin swirl brownies, I wanted brownies and I wanted pumpkin flavor.  I did not want pumpkin cheesecake brownies, however (been there, done that).  Most recipes for pumpkin swirl brownies actually mix the pumpkin with cream cheese before swirling.  This just dilutes the pumpkin flavor, so no thank you.

But then I started to wonder: is this for a reason? Does the cream cheese help stabilize the pumpkin? Would just plain pumpkin puree not set properly?

There’s only one way to find out — to the experimental kitchen!

This is one of those recipes that I thought about for a really long time.  I wanted to make one batter base and split it in two, adding chocolate to one side and pumpkin to the other.  If I used melted chocolate, the fat content would be much higher on the brownie side than the pumpkin side.  If I used cocoa powder, the flour-to-liquid ratio would be way different.

(These are the kind of things you think about for days when you’re both a scientist and a baker.)

And so, I set off with three recipes to test: one with cocoa powder (which makes the best brownies, in my opinion) in one batter and pumpkin in the other, one cocoa powder in one batter and pumpkin + additional flour in the other, and one with melted chocolate in one batter and pumpkin + additional oil in the third.

I never even got around to testing the last two options because the first one was just right.

square pan of pumpkin swirl brownies on an orange and yellow dishtowel.

Cocoa Powder vs Melted Chocolate in Brownies

Let’s pause here for a second to talk about my favorite subject… kitchen chemistry!  I mentioned above that melted chocolate would add more fat than cocoa powder.  Why is this? What’s the difference?  Let’s learn!

Kitchen Chemistry

Chocolate is composed of two parts: cocoa solids and cocoa butter.  Cocoa solids are responsible for the rich flavor, while cocoa butter brings the silky smooth texture.  Cocoa powder is mostly comprised of cocoa solids, containing only roughly 10% cocoa butter.  It’s packed full of chocolate flavor, but much lower in fat (and thus has a chalky texture).  Pure solid unsweetened chocolate, on the other hand, contains around 55% cocoa butter, resulting in the smooth, melty texture we expect from solid chocolate.

Because cocoa powder has a greater percentage of cocoa solids, it brings more chocolate flavor to baked goods.  Since this is a baked dessert, we don’t need the extra creaminess from the cocoa butter, and I really wanted to play up the chocolate flavor against the pumpkin, which is why my first attempt used cocoa powder, instead of melted chocolate.  Success!

pumpkin swirl brownies cut into squares in a springform pan.

Mix Pumpkin Into Brownie Batter

These are seriously, seriously easy brownies.  The base is the same as my simple fudgy brownie recipe, except we’ll hold off on adding any cocoa powder in the beginning. 

One of the reasons I really love this recipe is because it uses melted butter, so the whole thing can be whisked by hand.  No need to break out the mixer!

At this point, divide the batter into two bowls.  I did this by eye, but you can certainly do it by weight if you want to be exact!  To one bowl, we’ll add the cocoa powder.  The batter is pretty thick, so mix it in with a spatula rather than a whisk.  I also stirred in some chocolate chips — don’t skip this step!  The added texture from the bite of chocolate is A+.

To the other bowl, we’ll whisk in some pumpkin puree, cinnamon, and nutmeg.  You know, those “pumpkin spice” flavors. Except just the right amount.  I like pumpkin; I do not care for overbearing pumpkin spice.  This still tastes like pumpkin and not just nutmeg!

overhead view of orange and brown pumpkin swirl brownies on a metal dish.

Swirling Brownie Batters

There are a couple of options for how to combine the two batters.  You could make these as layered brownies, spreading all the chocolate batter on the bottom and the pumpkin batter on the top, ensuring an equal bite of chocolate and pumpkin in each.

Instead, I dropped dollops of alternating batters along the bottom of the pan, smoothing with the back of a spoon as I went.  When the bottom of the pan was covered, I added more dollops of batter on top.  Then I took a knife and ran it through both batters in an “S” pattern in each direction.

In the end, this meant that some of the brownies were mostly chocolate with a little bit of pumpkin.  Some were mostly pumpkin with a little bit of chocolate.  And some were a perfect mix of both.  In the end, I really liked this, because it lets everyone choose their own preferred chocolate-to-pumpkin ratio!

(Surprising no one, my husband and 3-year-old immediately reached for the chocolatiest ones, while I grabbed a nice orange one, full of pumpkin.  Everybody wins! Oh, and that bright orange color? Totally natural, from the pumpkin!)

side view of four pumpkin swirl brownies stacked on top of each other

Storing Pumpkin Brownies

Baked goods with fruit (in this case, the pumpkin) are more likely to spoil faster because of the increased moisture content.  These brownies will last just fine up to 4 days at room temperature, but for any longer, refrigerate in an air-tight container.

Or make them ahead of time and store them in the freezer for a pumpkin swirl brownie anytime you’d like!  Freeze precut brownies in a single layer, then combine in a freezer bag once frozen solid.

Because who’s to say that pumpkin desserts should only be enjoyed in the fall?  Make a batch now and enjoy them all year long!

overhead view of a stack of pumpkin swirl brownies with one bite taken out of the top brownie.
  • 9″ Square Baking Pan: You’ll want to use a metal, not glass, for these brownies – metal is a better conductor of heat.
  • Mixing Bowls: This set of glass mixing bowls is my favorite!
  • Whisk: A sturdy whisk makes a big difference in whisking together the butter and sugar.
  • Cocoa Powder: Use a good quality natural unsweetened cocoa powder – the higher fat content in better quality cocoa powder makes a big difference!
  • Cooling Rack: This wire cooling rack is sturdy enough to support the brownies in the pan, but folds down flat for storage.
side view of a tray of pumpkin swirl brownies highlighting the chocolate and pumpkin swirls.

Tips and Tricks for the Best Pumpkin Swirl Brownies

  1. Use Pumpkin Puree, Not Pumpkin Pie: Opt for canned pumpkin puree or make your own using sugar pumpkins. Don’t use pumpkin pie filling, which will be too sweet with the brownies!
  2. Opt for High-Quality Cocoa Powder: Investing in good-quality cocoa powder with a higher fat content provides better texture and keeps the brownies more moist.
  3. Line the Pan with Parchment Paper: Line your baking pan with parchment paper, leaving some overhang on the sides. This makes it easier to lift out the brownies after cooling.
  4. Cool Completely: Allow the brownies to cool completely in the pan on a wire rack before cutting – this helps them set so they don’t crumble.
  5. Chill for Clean Slices: For neat and clean edges, refrigerate the brownies for an hour or two before cutting. Use a sharp knife dipped in hot water for smooth edges.
  6. Freeze for Long Term Storage: The brownies can be stored at room temperature for 4 days, refrigerated for a week, or stored in an air-tight freezer-safe container in the freezer for up to 3 months.

More Pumpkin Desserts

a vertical stack of brownies swirled with pumpkin puree.

Pumpkin Swirl Brownies

Yield: 16 brownies
Prep Time: 15 minutes
Cook Time: 45 minutes
Total Time: 1 hour

Give your brownies a fall twist with these pumpkin swirl brownies! Easy, mix-by-hand chocolatey brownies mixed with pumpkin batter.

Ingredients

  • 1 cup (227 grams) unsalted butter, melted
  • 1 3/4 cups (347 grams) granuated sugar
  • 4 large eggs
  • 1 teaspoon salt
  • 1 teaspoon baking powder
  • 2 teaspoons vanilla extract
  • 1 2/3 cups (20 grams) all-purpose flour
  • 1/2 cup (84 grams) natural unsweetened cocoa powder
  • 1/2 cup (85 grams) chocolate chips
  • 1 cup (227 grams) pumpkin puree
  • 1 teaspoon cinnamon
  • 1/4 teaspoon nutmeg

Instructions

  1. Preheat the oven to 350 °F. Lightly grease a 9x9-inch square baking pan.
  2. Melt the butter in a large microwave-safe bowl for 30 second increments, mixing after each, until fully melted. Whisk in the sugar until well combined. Whisk in the eggs, one at a time. Use a rubber spatula or wooden spoon to stir in the salt, baking powder, vanilla extract, and flour.
  3. Divide the batter into two bowls. To one bowl, add the cocoa powder, stirring until just combined and no streaks of cocoa powder remain. Fold in the chocolate chips. Add the pumpkin puree, cinnamon, and nutmeg to the other bowl and whisk to combine.
  4. Scoop spoonfuls of each batter into the prepared baking pan, alternating between the chocolate and pumpkin. After distributing all batter, smooth the surface and use a knife to swirl the two batters together.
  5. Bake the brownies for 45 minutes, or until a tester inserted into the center comes out with just a few moist crumbs. Remove from the oven and cool on a rack before slicing and serving.

Notes

  1. Make sure the brownies cool completely in the pan before slicing.
  2. For neat and clean edges, refrigerate the brownies for an hour or two before cutting. Use a sharp knife dipped in hot water for smooth edges.
  3. Pumpkin swirl brownies can be stored at room temperature for up to 4 days, refrigerated for a week, or stored in an air-tight freezer-safe container and frozen for up to 3 months.

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Nutrition Information:
Yield: 16 Serving Size: 1 brownie
Amount Per Serving: Calories: 290Total Fat: 15gCarbohydrates: 38gSugar: 25gProtein: 4g

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Pumpkin Swirl Brownies: easy mix-by-hand chocolatey brownies swirled with pumpkin batter for a customizable fall treat!