Today Jenn Johns (that’s me!), shows you how to make a Geode Cake! A geode cake is a cake with a large carved indentation filled with graduated blue crystals. What puts this cake decorating tutorial over the top is the use of 100% edible gold leaf! This type of design has become super popular over the last year and I have had so many requests to make my version of it.
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I had a rock collection as a kid and I remember my favorite ones were the crystal ones . . . amethyst I think. I specifically remember being on a family vacation in Oregon, and finding tons of collector rocks at the Sea Lion Caves. They were in the souvenir shop, but hey, you can’t expect a beautiful crystal rock to be just laying around waiting to be picked up now can you?! I hope I’ve enlightened you with the idea of driving to the Oregon Sea Lion Caves to get collector rocks in the tacky souvenir shop. If I haven’t and you’re actually just here to learn how to make this cake, then carry on with the tutorial below. Since I had such a love for amethyst as a child, I really wanted to do this cake in shades of purple, but when I was practicing the cake on cake dummies I tried out both a purple geode and a blue geode. The blue geode stood out much better than the purple one did, but it was still really beautiful.
You can go about getting the rock candies on amazon like I did, or you could use hard candies that you have smashed into pieces. I tried smashing the large rock candy on the string with the end of a rolling pin, but it crushed to powder, rather than to small chunks like I wanted. I was able to find a large variety of shades of blue in the rock candy on a stick, so that made this project a little easier than it could have been.
A couple of years ago, I did a video tutorial on how to make your own rock candy. Who knew it would come in handy eventually!? You can find the detailed tutorial here, but keep in mind it takes a while to grow. . . like 2 weeks.
I love how perfect the rock candy stands in for crystals in this cake. I’ve found rock candy as a handy thing to have around and I have used it in a ton of cake designs, from candy cakes, to Penguin cakes, to Olaf cakes!
Gold leaf is a cake decorating element that I have been stunned by in the passed, so I knew that I had to put the packages I had to use when I decided on this cake. Golf leaf is crazy expensive, so you’ll want to be extra careful when setting out using it. The slightest movement of air can wrinkle the sheets and render them useless. Make sure the air conditioning is off and hold your breath! Golf leaf is so fragile it will stick to anything that touches it. It even gets a static charge to it. Don’t forget to use water prior to application on to the fondant- it’s the best thing for it to stick too, relatively wrinkle free. I’m not kidding when I say it’s finicky to work with. I hope these little tips make your first attempts at using it better than mine!
How to Make a Geode Cake (Geode Wedding Cake)
Ingredients and Materials:
- Prepared, stacked and buttercream covered 6″ and 8″ round cakes
- Fondant- white, blue
- 3 shades of blue rock candy on a stick
- Clear/white rock candy on a stick
- Light blue rock candy on a string (large pieces)
- Clear Piping gel
- Edible Gold Leaf
- Wooden dowels
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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!
- 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.
- 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.
- Pile the large chunk rock candy on a string on top of the cake as a cake topper.
- Keep cake in fridge until you are ready to serve . It is best consumed within 2-3 days.