These spider web brownies are everything I love in a Halloween treat—festive, fudgy, fun to make, and even more fun to eat. I take rich, jet-black brownies made with black cocoa powder and vegan chocolate chips, then stretch melted marshmallows over the top to create a spooky spider web. They’re the perfect addition to any Halloween spread and always get attention at parties.

Spider Web Brownies

Why You’ll Love This Recipe

These brownies are a total Halloween win, and here’s why I love making them every spooky season:

Simple Ingredients: I only use basic pantry staples—nothing complicated or hard to find.
Beginner-Friendly: From start to finish, the steps are straightforward and fun. Even the marshmallow web is easier than it looks.
Incredibly Fudgy: I use four eggs and plenty of melted chocolate to keep these brownies ultra-moist.
Jet-Black Color: Thanks to black cocoa powder, these brownies have a deep, spooky color that’s perfect for Halloween.
Festive and Fun: The melted marshmallow web adds a dramatic flair that turns heads and gets compliments.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

10 ounces vegan mini chocolate chips, divided
¼ cup black 10/12 cocoa powder
1 cup 1:1 gluten-free flour
½ teaspoon salt
4 eggs, room temperature
½ cup brown sugar
1 cup granulated sugar
2 teaspoons vanilla extract
½ cup marshmallows

Directions

I start by preheating the oven to 350°F and lining an 8×8-inch baking pan with parchment paper. I also lightly coat the sides with coconut oil.
In a small saucepan, I melt 1 cup of chocolate chips with olive oil over medium-low heat, stirring constantly, then set it aside.
In a medium bowl, I whisk together the black cocoa powder, gluten-free flour, and salt.
In a large bowl, I mix the eggs, brown sugar, granulated sugar, and vanilla extract. Then, I stir in the melted chocolate mixture.
I combine the dry ingredients with the wet mixture using a rubber spatula, just until blended, then fold in the remaining chocolate chips.
I pour the batter into the prepared baking pan and spread it evenly. I bake it for 34 to 40 minutes, until a toothpick inserted in the center comes out with moist crumbs.
Once baked, I let the brownies cool in the pan for an hour. They crack beautifully on top as they cool.
For the spider web, I microwave the marshmallows in 20-second intervals until soft and stretchy. Wearing food-safe gloves, I stretch and pull the marshmallows into web-like strands and place them over the brownies.
After the topping sets, I lift the brownies out using the parchment paper handles, let them finish cooling, and slice into squares.

Servings and Timing

This recipe makes 6 large servings (or 9 smaller squares if preferred).

Prep Time: 10 minutes
Cook Time: 40 minutes
Cooling Time: 1 hour
Total Time: Approximately 1 hour and 50 minutes

Variations

Regular Ingredients: I sometimes swap the gluten-free flour and vegan chocolate chips for standard ones when there are no dietary restrictions.
Nutty Twist: I love adding walnuts or pecans for crunch and extra flavor.
Extra Decorations: A plastic spider or mini marshmallow ghosts make these brownies even more Halloween-ready (just remember not to eat the plastic).
Flavor Boost: A pinch of instant coffee deepens the chocolate flavor.
Semi-Homemade: I’ve used brownie mix in a pinch—it works, though it won’t be as dark and rich.

Storage/Reheating

I store these brownies in an airtight container at room temperature for up to 5 days.
If I want them warm again, I microwave a brownie square for 10–15 seconds—just enough to bring back that gooey texture without melting the marshmallow web too much.

Spider Web Brownies

FAQs

How do I make the marshmallow spider web on top?

I melt marshmallows in short bursts in the microwave, then use gloved hands to stretch the melted marshmallow into thin strands. I carefully drape those strands across the brownies to form a web-like design.

What makes the brownies jet black?

The deep black color comes from black cocoa powder, which is ultra-dutched and darker than traditional cocoa. It also adds a smoother, less bitter chocolate flavor.

How do I make my brownies more fudgy?

I use four eggs, melt part of the chocolate, and avoid overmixing. These steps give me that dense, moist, fudgy texture I love.

Can I make these brownies in advance?

Absolutely. I often bake them a day ahead, then add the marshmallow spider web before serving to keep the topping fresh and sticky.

Do I have to use food-safe gloves for the marshmallow web?

I highly recommend it. The melted marshmallow is sticky, and gloves make it easier to handle and shape into delicate web strands without making a mess.

Conclusion

These spider web brownies are everything I want in a Halloween dessert—rich, fudgy, festive, and fun to make. Whether I’m bringing them to a spooky party or making them just because, they always impress and satisfy. With simple ingredients and a little creativity, I turn a classic brownie into a show-stopping Halloween treat.