How To Make a Beautiful, Trendy Geode Cake

The geode cake trend is one of the most beautiful we’ve ever seen. Seriously, food trends can come and go, but we hope the geode cake is here to stay! Rainbow foods and galaxy macaroons are safely on their way off your Instagram feeds, but we would bet there are still geode cakes. Why are these cakes still so popular after months? Most food trends don’t last a month, let alone almost a year! Well, once you see this beautiful cake design, you will completely understand why bakers everywhere are going nuts for this cake design. Let’s just say it totally rocks. (Get it?)

Geode cakes are special because of a hole or slice made in your cake. No, that doesn’t mean you get to eat a slice out of your cake – although we’re certainly not stopping you. This hole serves a purpose: to house a glimmering array of edible geodes within your lovely cake.

We’re sure you know this, but just in case we’ll let you know that a geode is another word for a rock. And our favorite kind of rock can be found in this cake: rock candy.

Beautiful rock candy is responsible for giving this super chic cake it’s geode appearance, making the entire cake 100% edible. It’s pretty to look at AND you can eat it? Does it get any better than that?

The best part is, although this cake looks super complicated, it’s actually incredibly easy to pull off. You only need about five or six ingredients (not counting the actual cake itself) and making this cake look like so much fun. Bakers are going to flip for this recipe.

Let it be known that two different types of rock candy are required: string rock candy and regular rock candy. Regular rock candy is the classic kind we know, on a stick. String rock candy is loose candy and is larger than the classic variety. You want both to mix up the look of the geode.

Also, as far as coloring your cake goes, feel free to go nuts! You don’t have to stick to this palette of sky blue. We’ve seen gorgeous geodes in purples, pinks, greens, oranges – you name it! Just make sure you use both light and dark colors within the palette to give the “rock” and the whole cake some realistic variety.

What do you think about this trendy cake? Share your photos of you geode cake in the comments section below.

Geode Cake


  • 8″ cake, frosted

  • 6″ cake, frosted

  • Clear piping gel

  • String rock candy

  • Regular rock candy

  • Fondant (dyed two different colors)
  • Edible gold leaf


  • Fondant smoother
  • Fondant cutter or pizza cutter
  • Sharp dowel
  • Saw or sharp knife


  1. Prepare cakes and cover in a thin layer of buttercream. Have 6″ cake on a small, thin cardboard cake board, and the 8″ cake on a large, white cake board.
  2. Roll out two long logs of white fondant and a long log of blue fondant and twist together. Continue to twist and roll fondant together until it is marbled. Using a large fondant rolling pin, roll fondant out flat into a circle at least 14″ in diameter for the small cake, and at least 16″ in diameter for the larger cake.
  3. Drape fondant over top of each cake and smooth flat with a fondant smoother. Cut any excess away with a sharp knife or pizza cutter.
  4. Place three wood dowels into the larger cake and cut flush to the top of the cake. Stack with smaller cake on top of the support dowels.
  5. Use an edible ink pen to draw a long oval shape onto the cake, with half on the top and half on the bottom tiers. Use a sharp knife to remove a deep groove amount of cake.
  6. Cover the exposed cake in buttercream, and then piping gel. Start in the center with the darkest blue rock candies and work outwards with the lighter candies.
  7. To use the gold leaf, cut pieces into small strips by placing sheet of gold in between 2 sheets of transfer paper. Gold leaf is extremely fragile and will move at the slightest movement of air. Be warned!
  8. Brush application area of fondant with water and press gold leaf to that area. Using a large, dry, makeup brush, press the gold leaf down on to the wet fondant area. Fill in any gaps between the gold and the crystals with additional clear crystals.
  9. To make the border around the bottom of both cakes, pipe on a generous amount of piping gel at the bases and start with the darkest blue at the bottom, working your way up to the lightest.
  10. Pile the large chunk rock candy on a string on top of the cake as a cake topper.
  11. Keep cake in fridge until you are ready to serve.  It is best consumed within 2-3 days.