Halloween brownies turn a dependable pan of rich cocoa bars into a party-ready dessert with two playful finishes. The batter combines granulated and brown sugar for deep flavor, while white royal icing creates crisp spiderwebs and simple mummy bandages after the brownies cool. This recipe makes 24 pieces, so one batch is practical for a classroom table, neighborhood gathering, or dessert buffet. Cut a mix of squares and rectangles to make both designs without changing the brownie recipe.
Thank you for reading this post, don't forget to subscribe!What Are Halloween Brownies?
These are cocoa brownies baked in a 9-by-13-inch pan, cooled completely, and decorated with firm white royal icing. Square pieces become spiderweb brownies, while rectangular pieces become mummies with piped bandages and candy eyeballs. The decoration is graphic but straightforward, and the same icing works for both shapes.
Why This Recipe Works
Melted butter carries the cocoa flavor, and the combination of granulated sugar and packed light brown sugar gives the brownies sweetness with a subtle caramel note. Adding the eggs one at a time helps the batter become glossy. Cooling the slab before cutting protects the edges, while dense royal icing keeps the piped lines defined.
How to Make Halloween Brownies
Quick Overview
Prepare the lined pan, mix the cocoa batter, bake until the top is crackly, and cool the slab fully. Cut 24 brownies in square and rectangular shapes. Make one batch of royal icing, then pipe webs on the squares and mummy ribbons on the rectangles before adding candy eyeballs.
Ingredients
- 2 sticks unsalted butter, room temperature, plus more for the pan
- 1 1/4 cups unbleached all-purpose flour, plus more for the pan
- 1 1/4 teaspoons kosher salt
- 1 1/2 cups granulated sugar
- 1/2 cup light brown sugar, packed
- 1 cup unsweetened cocoa powder
- 4 large eggs, room temperature
- 2 teaspoons pure vanilla extract
- Candy eyeballs, for decorating
- 2 cups confectioners’ sugar
- 2 1/2 tablespoons meringue powder
- 1/4 cup water
Ordered Method
- Preheat the oven to 325°F. Butter a 9-by-13-inch baking pan, line the bottom and long sides with parchment with a 2-inch overhang, then butter and flour the parchment.
- Whisk the flour and salt together. Melt the butter in a heatproof bowl set over, but not in, simmering water; remove from the heat and whisk in both sugars and then the cocoa powder.
- Whisk in the eggs one at a time until the mixture is glossy, mix in the vanilla, then stir in the flour mixture just until combined.
- Spread the batter evenly in the prepared pan and bake for about 30 minutes, until the top is crackly and a tester inserted in the center comes out clean.
- Cool in the pan on a wire rack for 30 minutes, lift out by the parchment, cool completely, and cut into 24 squares or rectangles.
- Beat the confectioners’ sugar, meringue powder, and water on low speed for 7 to 8 minutes, until the royal icing is fluffy but dense.
- Pipe thin connected lines on square brownies to form spiderwebs.
- Pipe ribbons of icing back and forth on rectangular brownies to form mummy bandages, then add candy eyeballs.
“The Halloween Brownies with Spiderweb and Mummy Icing turned out amazing. My kids asked for seconds. Saving this one!”
Serving Ideas
Arrange the spiderweb squares and mummy rectangles together so the two designs read clearly. A simple platter keeps the white icing visible against the dark brownies. Because the batch yields 24 pieces, it also works well when each brownie needs to be placed on an individual napkin or dessert plate.
Tips and an Optional Variation
Let the brownies cool completely before cutting or decorating; warmth can soften the icing and blur the web lines. For cleaner edges, lift the slab out with the parchment and wipe the knife between cuts. Keep the piping opening small for webs, then use wider back-and-forth ribbons for the mummy design.
Optional variation: Decorate the entire batch as spiderweb squares if you do not have candy eyeballs. This changes only the visual finish; keep the brownie batter, baking time, and royal icing exactly the same.
Storage and Make-Ahead Notes
The baked brownies can be prepared up to two days ahead and kept well wrapped in an airtight container at room temperature. Royal icing can also be made ahead, covered directly on its surface, and refrigerated. If the brownies are already decorated, store them in a single layer at room temperature for up to two days so the piped designs stay intact.
Easy Halloween Brownie Recipe for a Crowd
One 9-by-13-inch pan produces 24 decorated pieces, which makes this recipe useful for a larger gathering without requiring multiple batters. Use the parchment overhang to move the cooled slab, then plan the cuts before slicing so the finished assortment includes both squares and rectangles.
Spooky Brownie Recipe Decorating Ideas
The two canonical finishes rely on white royal icing: connected curved lines for spiderwebs and overlapping ribbons for mummy bandages. Candy eyeballs complete the mummy pieces. Keeping the decoration monochrome makes the shapes easy to recognize and avoids adding unsupported toppings to the primary recipe.
Halloween Brownies FAQs
Can I decorate warm brownies?
No. Cool the slab completely before cutting and piping so the royal icing stays dense and the lines retain their shape.
How many brownies does one batch make?
The recipe yields 24 brownies from one 9-by-13-inch pan.
“New family favorite! This Halloween Brownies with Spiderweb and Mummy Icing was so flavorful and ridiculously easy. Crowd-pleaser for sure.”
What makes the mummy design?
Pipe white royal icing back and forth in overlapping ribbons across rectangular brownies, then finish each one with candy eyeballs.
Can I make the brownies ahead?
Yes. Keep the baked or decorated brownies well wrapped at room temperature for up to two days.
Final Thought
A single cocoa-brownie batter and one bowl of royal icing produce a varied Halloween platter without complicating the method. Cool the brownies fully, keep the piping deliberate, and use the cut shape to guide each decoration.
Halloween Brownies with Spiderweb and Mummy Icing
Ingredients
Ingredients
- 2 sticks unsalted butter room temperature, plus more for the pan
- 1 1/4 cups unbleached all-purpose flour plus more for the pan
- 1 1/4 teaspoons kosher salt
- 1 1/2 cups granulated sugar
- 1/2 cup light brown sugar packed
- 1 cup unsweetened cocoa powder
- 4 large eggs room temperature
- 2 teaspoons pure vanilla extract
- candy eyeballs for decorating
- 2 cups confectioners' sugar
- 2 1/2 tablespoons meringue powder
- 1/4 cup water
Instructions
Instructions
- Preheat the oven to 325°F. Butter a 9-by-13-inch baking pan, line the bottom and long sides with parchment with a 2-inch overhang, then butter and flour the parchment.
- Whisk the flour and salt together. Melt the butter in a heatproof bowl set over, but not in, simmering water; remove from the heat and whisk in both sugars and then the cocoa powder.
- Whisk in the eggs one at a time until the mixture is glossy, mix in the vanilla, then stir in the flour mixture just until combined.
- Spread the batter evenly in the prepared pan and bake for about 30 minutes, until the top is crackly and a tester inserted in the center comes out clean.
- Cool in the pan on a wire rack for 30 minutes, lift out by the parchment, cool completely, and cut into 24 squares or rectangles.
- Beat the confectioners' sugar, meringue powder, and water on low speed for 7 to 8 minutes, until the royal icing is fluffy but dense.
- Pipe thin connected lines on square brownies to form spiderwebs.
- Pipe ribbons of icing back and forth on rectangular brownies to form mummy bandages, then add candy eyeballs.
