This chocolate spider web cake features three layers of chocolate cake frosted in a simple chocolate American buttercream and decorated with melted marshmallow spider webs!
It’s Halloween time!
It’s time to start planning out candies to buy, decadent treats to make, and boozy cocktails to share.
There are no flavor restrictions during Halloween. Anything goes!
But of course, it’s never a bad idea to stick to a Halloween classic- CHOCOLATE!
Spider Web Chocolate Cake
Four years ago I shared this black sesame cake with orange spider webs.
It was a hit for black sesame fans! But, I understand black sesame is a not a universally loved flavor.
This year, I’m sharing an easy marshmallow web cake everyone can enjoy… because who doesn’t like chocolate cake?!
Easy Chocolate Cake
Instead of coconut oil, I swapped in grape seed oil. Grape seed oil has a neutral flavor and a moderately high smoking point. It keeps the cake soft and moist.
Feel free to sub in vegetable oil or canola oil. However, do not use olive oil. Olive oil’s strong flavor will alter the cake.
Mix cake batter together by hand or with the help of a stand mixer (or electric hand mixer).
Unsweetened Cocoa Powder Options
The chocolate cake is flavored with cocoa powder and intensified with a touch of instant espresso powder.
There are several choices of unsweetened cocoa powder to choose from:
- Natural Cocoa
- Dutch-Processed (or “alkalized”) Cocoa
- Black Cocoa
I used natural unsweetened cocoa powder from Trader Joe’s.
Sometimes labeled as unsweetened cocoa powder or just cocoa powder, this is the standard cocoa powder you’ll find at the super market.
This refers to natural cocoa that has been processed with alkali. This process lowers the acidity of the cocoa and reduces the bitter flavor of unsweetened cocoa.
There are dozens of varieties within the Dutch-processed category. Each brand usually puts their own unique twist or spin on it.
For example, you may seen Hershey’s “Special Dark” which is a blend of natural and Dutch-processed cocoas.
Black cocoa is a super Dutch-processed cocoa. It is processed until the cocoa turns almost black in color.
NOTE: Don’t confuse unsweetened cocoa powder with “hot cocoa mix.” That mix contains sugar, milk, and stabilizers.
How to make Marshmallow Spider Webs
Marshmallow spider webs are simple to make. However, I must warn you, marshmallow webs are SUPER messy.
It’s best to work on a surface that you can easily wash or wipe with a damp cloth.
Store-bought marshmallows work best for this technique. I have tried using homemade marshmallows, but failed each time. The stabilizers and amount of gelatin in store-bought marshmallows is key.
Any size marshmallows will work, from mini to jumbo sized. Simply place marshmallows in a microwave safe container. Microwave for 20-30 seconds until marshmallows have puffed up.
At this point, the marshmallow mixture will be VERY HOT. Carefully remove from the microwave and stir marshmallow mixture until smooth.
Allow the marshmallow mixture to cool and thicken, about 3 minutes. You’ll end up with this shiny, glossy, and super stringy goop.
Use two forks to pull out about a tablespoon of the marshmallow mixture. Stretch and pull into strands and gently drape over the top and sides of the frosted cake.
Alternatively, you may use your fingers. But remember, it’ll be messy!
Serve the cake as is with marshmallow webs. Or, attach plastic spiders to the cake for extra spunk!
Here are some options for different sized spider and critters for sale on Amazon:
- This variety pack of fake toy spiders and bugs looks fun.
- These realistic plastic spiders are scary with their bright red eyes.
Cake to Buttercream Ratio:
I prefer more cake and less buttercream. The chocolate buttercream recipe listed below makes enough to fill each layer with about 1/3 cup of frosting, crumb coat the outside, and apply second buttercream coat.
Double the buttercream recipe if you like your cakes heavy on the frosting.
Chocolate Spider Web Cake
- 2 cup (260 g) all-purpose flour
- 1/2 cup (40 g) unsweetened cocoa powder
- 1/2 Tablespoon instant espresso powder
- 1 teaspoon baking powder
- 1 teaspoon baking soda
- 1 teaspoon kosher salt
- 1/2 cup grapeseed oil, or vegetable oil
- 1 1/4 cup (250 g) granulated sugar
- 2 large eggs, room temp
- 1 teaspoon pure vanilla extract
- 2/3 cup (150 g) whole milk
- 1 cup (240 g) sour cream
Simple Chocolate Buttercream:
- 1 cup (225 g) unsalted butter, room temp
- 3 cup (340 g) confections sugar
- 1/2 cup (40 g) unsweetened cocoa powder
- 1/4 teaspoon kosher salt
- 2 Tablespoon whole milk
- 3 oz (85 g) marshmallows (12 regular sized, or 1 1/2 cup mini marshmallows)
- Preheat oven to 350°F. Line three 6-inch round cake pans with parchment paper. Lightly grease and set aside.
- In a large bowl, whisk together flour, cocoa powder, espresso powder, baking powder, baking soda, and salt. Set aside.
- In the bowl of a stand mixer fitted with a paddle attachment, beat together oil, sugar, eggs, and vanilla until well combined.
- On low speed, alternate adding dry flour mixture and milk. Add about 1/3 of flour mixture. Mix on low speed until almost incorporated. Follow with half of milk. Mix on low. Repeat adding another 1/3 of flour and remaining half of milk. Scrape down bowl as needed to ensure thorough mixing. Add sour cream and remaining 1/3 flour. Mix on low speed until there are no longer any streaks of dry flour.
- Divide batter among prepared cake pans (about 370 g per cake pan). Level batter. Bake for 25-28 minutes until toothpick inserted in center of cake comes out clean. Rotate cakes midway through baking.
- Allow cake to cool in pan for 5 minutes before unmolding. Run mini offset spatula around perimeter of cake to loosen from pan, if necessary. Let cakes cool to room temperature on wire rack.
Simple Chocolate Buttercream:
- In the bowl of a stand mixer fitted with a paddle attachment (or using an electric hand mixer), cream butter until smooth. Add confectioners' sugar, cocoa powder, salt, and milk. Mix until buttercream is smooth.
- Level cooled cakes as needed. Place on cake layer on cake stand or serving plate. Spread about 1/3 cup of chocolate buttercream over cake.
- Place second cake layer on top, spread buttercream, and top with third cake layer.
- Spread a thin layer of buttercream around the sides of the cake to seal in the crumbs (crumb coat). Place in the fridge and allow to chill for 20 minutes to set buttercream.
- Coat cake with another layer of buttercream. Keep in the fridge until ready to decorate with marshmallow webs.
- Place marshmallows in a microwave safe bowl. Microwave for 20-30 seconds until marshmallows have puffed up. Stir and until smooth. Allow to melted marshmallows to cool and thicken, about 3 minutes.
- Use two forks to pull out about a tablespoon of marshmallow mixture. Stretch and pull into strands and gently drape over top and around the sides of frosted cake. Alternatively, use your fingers to stretch and drape marshmallows over cake.
- Chocolate cake can be baked in advance. Cool to room temperature, then tightly wrap in plastic wrap. Keeps at room temperature for one day. For longer storage, keep cake in the freezer for up to two weeks. To defrost frozen cake, allow to thaw at room temperature overnight.
- Store-bought marshmallows work best in this recipe.
- Unsweetened cocoa powder brand/variety will determine the color of finished chocolate buttercream. I used "natural unsweetened cocoa powder."
- If chocolate buttercream color is not to your liking, intensify the color using gel colors, such as AmeriColor Chocolate Brown.