The Spooky Black Geode Cake

This cake was, shall we say, a freewheeling design. I had a vague idea of what I wanted to do for my son’s annual Halloween-themed birthday party – an all-black cake (inside and out) with bugs somehow involved (because eight-year-old boys, et cetera), and I thought maybe it’d be cool to have the bugs sort of coming out of the cake as if they’d been inside, but when I got to the part where I’d actually do that, I was stumped.

I wanted a crack in the cake of some sort, but didn’t want it to look like, you know…a mistake.

And then I remembered the geode cake. It’s all over Pinterest these days, and I’ve been dying to try one, and you know what geodes have?! CRACKS. (Sort of; you know what I mean.)


Spooky Black Geode Cake (plus bugs!) it was.

how to make a spooky geode cake for halloween

Improvisation, whee!

The flavor of cake I went for was Devil’s Food with dark chocolate icing and a strawberry jam center, but of course for the cake part you can do as you will. I do think this particular look benefits from a dark interior, though.

What You Need:

  • 1 package Devil’s Food cake mix (plus the eggs and oil you need to make it according to package instructions).
  • 1 can dark chocolate frosting
  • 1 cup strawberry jam
  • 1 package black fondant
  • A few sticks each of red and clear rock candy
  • Plastic bugs of your choice (washed and rinsed well)

steps for making a double layer fondant cake

Step 1. Cook the cake (in two round pans) according to package directions. Once cooled, wrap in plastic wrap and refrigerate a few hours or overnight.

how to make a cake with jam in the middle

how to make a cake with jam in the middle

Step 2. Using a very sharp knife, level the top of each cake to create a perfectly flat surface. Spread jam onto just the top of one cake, then place the other neatly on top.

how to make a cake with jam in the middle

Step 3. Spread a thin layer of frosting all over the outside of the cake.

how to make a black fondant cake

how to make a black fondant cake

Step 4. Roll out the black fondant into a thin layer (approx 1/4″), and gently drape it over the top of the cake, then pull it down along the sides and use a sharp knife to cut off the excess. If you’ve never done this, you might want to watch a quick tutorial.

how to make a black geode cake

Step 5. Now, the geode crack. Basically, just hack a piece out of the cake – as big or as small as you want to go – then spread a thin layer of frosting over the exposed surface. Note: I wish I had used vanilla frosting here, since it would be easier to cover with white crystals, but hey.

how to make a black geode cake

how to make a black geode cake

Step 6. Break up the rock candy into pieces – you want pieces of varying size for the most natural effect. When you layer on the candy, remember that the darker color should go on the inside for depth.

how to make a black geode cake

Step 7. Add spiders and optional bloody knife, and there you go: Spooky Black Geode Cake. With bugs.




"Cave Of Wonders" Cake (With Rainbow Interior)

I want to be humble about this one, but it took me five hours, so I’m not going to be. (Granted, the creation process might have been slowed down ever-so-slightly by the fact that I was catching up on the 2-part season finale of The Bachelorette while fondant-ing, but STILL.)


"Under The Sea" Cake

This was the very first fondant cake I ever made, and kicked off what turned out to be a four-years-long (and still kicking) obsession.


"Spooky Ghost" Cake

Spooky and somehow also…quite cute, really.


"Moana" Cake

A few months before my daughter’s third birthday, I asked my daughter what she wanted for her third birthday – fully aware, of course, that she was going to change her mind approximately 1,352,534 times before the day actually arrived.

“Moana cake,” she said. Like, immediately. With zero pause for contemplation. Then she thought for a moment, and added, “And candy.”

Very well.

A month or so later, I asked her again. “Honey, have you thought about what you want for your birthday?”

“Moana cake. With sprinkles.”

And then, last week: “Are you sure there’s nothing else you want for your birthday? Just Moana cake?”

“I’m going to have a Moana cake and I’m going to EAT IT.”

I think it’s safe to say there was a little bit of pressure associated with this cake.


"Bloodshot Eyeball" Cake

Oddly enough (or, I don’t know, perhaps not oddly at all) there isn’t much in the way of instructions on the Internet re: how to create an eyeball out of fondant, so I started with this general idea from The Joys of Boys, and then ended up more or less improvising to get the effect I wanted.


"Tie-Dye Rainbow" Cake


powered by chloédigital