The At-Home Geode Cake

It's Monday and we are going to make a cake.  

Oh, but not just any cake.  A truly Pinterest-worthy, sure-to-be-the-envy-of-Instagram, and slightly reminiscent of Barbie's dream house, cake.  It is all very fancy and wonderful.  

Let's begin. 

First, let's listen to me rant once again about how much I ardently despise cake-making, and then allow me to tell you why, all of a sudden, I cannot stop making these trendy, candy-crusted objet d'arts. 

I have always hated making cakes.  I once made a wedding cake and solemnly vowed to never approach that daunting task again.  I avoid layer cakes like the plague.  Cupcakes are splendid and sheet cakes will always hold a place in my heart, but layer cakes...they are a world all their own.  A very finicky, gravity-defying, anxiety-inducing world.  

Not exactly my happy place. 

However, when the time came for my baby sister to graduate high school, I decided to exchange my scruples for a turntable and get to work on my very own Pinterest masterpiece. 

Before we can start turning out bedazzled cakes, we have to arm ourselves with a few tools.

Despite my lack of enthusiasm for cake-decorating, I have done a fair bit of practicing, and these are a few of the things I have found to be absolutely essential.  

First, you are going to need a turntable.  A turntable is a must when it comes to getting layer cakes frosted smoothly and evenly.  This is the tool that will take your cake game to the next level.  They are super affordable and, as kitchenwares go, they are not overly difficult to store.

Second, you will want to arm yourself with a couple offset spatulas of varying sizes. 

Thirdly, buy yourself an icing smoother.  This will give you that enviable, smooth finish. 

Lastly, you are going to need a good supply of wax paper and paper towels.  LOTS of paper towels.

Those are what I consider to be the basics for baking layer cakes.  That's our hardware.  However, geode cakes require a few pieces of more specialized software. 

Rock candy.  The kind that has an evil, unseen string inside.  Here's the color I used, but of course you can use any color you like for your geode masterpiece. 

Rock sugar.  When set atop your buttercream, this translucent rock sugar will take on a bit of the cake's hue and give your geode some gradation.

Edible gold leaf.  Make sure you buy EDIBLE gold leaf, as much of it is used for crafting and not eating.  

Gold sugar.  A sprinkling of this edible pixie dust is the perfect finishing touch! 

Food coloring.  I highly recommend using professional grade food coloring, especially when you are trying to achieve a really vibrant color.  It is much more economical and it prevents the frosting from taking on a icky, chemical flavor.  This is the color I used for my cake. 

When I am making layer cakes such as this one, I always bake my cakes the day before I plan on decorating them.  This gives the cakes themselves a bit of time to firm up and dry out a bit which will make them ever so much easier to work with. 

I also almost always lay aside my qualms and buy a couple boxes of cake mix.  I know, I am making cakes from a box.  The horror...

Because making a layer cake is pretty time-consuming and definitely messy, I go simple when it comes to the actual cake.  I have also found that, for whatever reason, the cakes from a mix tend to be a bit sturdier.  However, if you want to make your cakes yourself, I will cheer you on from afar and offer this recipe. 

The greatest secret to success when it comes to layer cakes is simply time and patience.  I know, it is hard, but greatness comes at a cost. 

After your cakes have rested overnight, you are going to do some slicing, stacking, and crumb-coating. 

This is also the time to make our wax-paper base.  Cut a large square of wax paper and fold it over on itself until you have formed a flat cone.  Then, use scissors to cut a rounded edge, and unfold to form a circle of wax paper about 2-inches longer than the diameter of your cake.  This will lay atop your turntable and under your first layer of cake.  Here's a short video of what this folding process looks like. 

A crumb coat is a very thin layer of icing that will seal in any crumbly edges and act as a slip of sorts so that none of our layers are visible through the second layer of buttercream.  Please, please, do not skip this step.  That would be a bad, bad thing.  I might be speaking from experience.

*sigh*...I am definitely speaking from experience. 

Sure, it's an extra step, but you wouldn't go out without underwear would you?  So, don't let your cake baby either. 

Now comes the patience part.  You are going to need to give that nearly-naked cake some quality time in the refrigerator.  This step will do a couple of things that will make our future lives so much better. 

First, the chill time will stiffen up the cake layers and harden the layers of buttercream so that there is no slipping or sliding.  Second, the crumb coat we applied will also harden as it chills, so that none of that buttercream, or the crumbs we covered, will be able to mix in with our final coat. 

After the cake has had a chance to chill, it is time for the final coat of buttercream.  It will look like way too much frosting, but trust me, you are going to use every last little bit. 

Pile all the frosting on the top of the cake and use one of those little off-set spatulas to work it down the sides.  Once you have the frosting over most of the cake, set your smoother against the side of the cake and spin that turntable.  This will give you that lovely, smooth finish.  It is going to take a few minutes to get it just right, so do not give up prematurely.  Use the smoother on the top of the cake to even out the surface as well, working the excess frosting off and down the sides and smoothing it in.  I always end up with one "blemish" on the top of my cakes, but I just let that direct me to the ideal geode placement! 

Use a sharp knife to cut a wedge out of the top and partway down the side of the cake and use the tiniest of your off-set spatulas to cover the exposed cake with frosting.  Do not bother striving for perfection here, because we are going to cover it all up with glitz and glam in the end. 

Set a few pieces of rock candy into the center of your cake cavern, pushing them into the cake so that they hold fast. 

Then, sprinkle the rock sugar around the rock candy, building the geode. 

Remove any stray pieces of fallen sugar, then carefully place the gold leaf. 

I will be perfectly honest with you.  This part sucks.  I hate working with gold leaf, but thankfully it does not have to be perfect.  The best trick I have found is using a toothpick to lift the gold leaf from the paper.  This will also help you lay it down on the cake a bit, but it will still require a bit of fussing and fanagling to get it right.  Just turn on the spa playlist and breathe.

After the gold leaf is in place, sprinkle the cake with a generous dose of gold sugar.  Now you are just about done.  

However, we still need to address that inevitably messy bottom edge. Not to worry.  This is my favorite little trick that makes me feel like a rocket scientist even though I am really just a 23-year-old with hot pink fingers. 

Use two large, metal spatulas and a lot of prayer to transfer the cake, wax paper bottom included, to your selected cake stand. 

Then, use a very sharp paring knife to trace along the edge of the wax paper, getting as close to the cake as you possibly can.  After you have gone along the entire perimeter of the cake, slice down the edge of the wax paper ring and pull it away.  Taa-daa!  A perfectly clean edge. 

It is so satisfying! 

If you are looking for a little extra glitz, place a few pieces of rock candy around the bottom edge of the cake. 

Now, we come to the fun part. 

Let's eat our masterpiece! 

If you have a strong urge to keep staring at your cake and telling every bystander, "I made this," do not feel badly.  I get you.  

If Barbie's dream house was a cake, this would be it. 

Just look at us, making our very own geode cakes like (wait for it...) rockstars.  Heeheehee.  At least two people are laughing right now and one is most definitely my dad. 

Sincerely, 

Pedantic Foodie

Photography with the very talented Esther Bain.  Be sure to check out her amazing Instagram! 

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AT-HOME GEODE CAKE

serves 10-12

FOR THE CAKES 

Being that this cake is a little labor-intensive, I like to take a small shortcut by using boxed cake mixes.

• 3 boxes vanilla cake mix
• plastic wrap
• wax paper 
• cake turntable 
• offset spatulas 
• 1 heaping cup of rock candy 
• 1/4 cup crystalized rock sugar 
• 5 sheets edible gold leaf 
• gold sanding sugar, optional  

Cook's Note: It is especially important that you bake your cakes the day before you plan on assembling your cake. 

Make the batter according to the box's instructions, then, grease and flour 3 8-inch cake pans and use one mix per pan. 

Bake according to the box's instructions, then allow the cakes to cool completely.  Wrap in plastic wrap and allow to sit overnight. 

The next day, prepare the first batch of swiss buttercream.  

FOR THE SWISS MERINGUE BUTTERCREAM [ CRUMB COAT ]

recipe adapted from King Arthur Flour

• 1 1/4 cups granulated sugar 
• 4 large egg whites 
• 1/4 teaspoon sea salt 
• 16 ounces unsalted butter, softened 
• 2 teaspoons vanilla extract 

Fill a 2-quart saucepan with about an inch of water and place over high heat; bring to a simmer. 

Combine granulated sugar, egg whites, and sea salt in the bowl of your stand mixer.*

Cook's Note: Wipe the bowl clean with a damp paper towel and dry thoroughly before using. 

Place the mixing bowl over the pan of simmering water, being sure that the water does not touch the bottom of the bowl.  

Warm, whisking constantly, until the mixture reaches 160 degrees F.  An instant-read thermometer is essential here. 

Return the bowl to your stand mixer fitted with the whisk attachment and whisk on high speed until stiff peaks form.  This will take a good bit of time, but do not rush this step. 

Cook's Note: As the mixture whips, it will cool down, preparing it to accept rather than melt the coming butter. 

Reduce the speed to medium high and begin adding the butter, about 1 tablespoon at a time.  Make sure each addition of butter is thoroughly incorporated before adding the next piece. 

Cook's Note: If the butter begins to melt, this is a sign that the mixture is too warm.  Simply stop mixing, and transfer the bowl to the refrigerator.  Cover with plastic wrap and refrigerate for 10-15 minutes, until the mixture is cool and stiff.  Beat for 1 minute to loosen the buttercream before continuing with the remaining additions of butter. 

After all the butter has been incorporated, mix in vanilla extract.  Set the buttercream aside while you prepare the cake layers. 

Unwrap the cakes.  Use a large, serrated bread knife to even out the top of each cake, creating a fat surface.  Then, slice each layer lengthwise, creating six, even layers.  You will only be using five of these six layers.  I often have one that is a bit uneven or that cracks when lifted, so this extra layer provides a bit of insurance. 

Cut a large square of wax paper and fold into a flat cone.  Then, use a sharp pair of scissors to round the end of the cone.  Unfold, forming a circle 10-inches in diameter.  Here is a video of this process. 

Lay the wax paper out onto your turntable and lay the first layer of cake atop the wax paper.  

Use an off-set spatula to spread a layer of icing over each layer, stacking the cakes as you go.  Be sure to top the cake with a bottom layer, flipping it over so that you have a flat surface free of crumbs. 

After you have all five layers in place, pile the remaining buttercream atop the cake and use an offset spatula to slowly bring the buttercream down the sides.  Slowly spin the turntable, running the cake smoother along the sides of the cake and across the top so that you have an evenly-frosted smooth cake.  Place the cake in the refrigerator for 1-2 hours; until the buttercream is hard. 

In the meantime, prepare the second batch of buttercream. 

FOR THE SWISS MERINGUE BUTTERCREAM [ FINISHING COAT ]

recipe adapted from King Arthur Flour

• 1/2 cup + 2 tablespoons granulated sugar 
• 2 large egg whites 
• pinch of sea salt 
• 8 ounces unsalted butter, softened 
• 1 teaspoon vanilla extract  
• 1 teaspoon rose food color

Fill a 2-quart saucepan with about an inch of water and place over high heat; bring to a simmer. 

Combine granulated sugar, egg whites, and sea salt in the bowl of your stand mixer.*

Cook's Note: Wipe the bowl clean with a damp paper towel and dry thoroughly before using. 

Place the mixing bowl over the pan of simmering water, being sure that the water does not touch the bottom of the bowl.  

Warm, whisking constantly, until the mixture reaches 160 degrees F.  An instant-read thermometer is essential here. 

Return the bowl to your stand mixer fitted with the whisk attachment and whisk on high speed until stiff peaks form.  This will take a good bit of time, but do not rush this step. 

Reduce the speed to medium high and begin adding the butter, about 1 tablespoon at a time.  Make sure each addition of butter is thoroughly incorporated before adding the next piece. 

After all the butter has been incorporated, mix in vanilla extract. 

Remove 1/4 cup of the prepared buttercream from the bowl and set aside.  Pile the remaining buttercream atop the chilled cake and use an offset spatula to slowly bring the buttercream down the sides.  Slowly spin the turntable, running the cake smoother along the sides of the cake so that you have an evenly-frosted smooth cake.  It is going to take a few minutes to get it just right, so do not give up prematurely.  Use the smoother on the top of the cake to even out the surface as well, working the excess frosting off and down the sides and smoothing it in. 

Use a sharp knife to cut a wedge out of the top and partway down the side of the cake and use the tiniest of your off-set spatulas to cover the exposed cake with the reserved buttercream.  Do not bother striving for perfection here, because it will be filled in with candy. 

Set several pieces of rock candy in the cavern and fill in with crystalized sugar.  Use a toothpick to lift the gold leaf onto the edges of the geode.  Sprinkle the cake with gold sugar, if desired.  

Use two large metal spatulas to lift the layer cake and wax paper base onto a cake stand.  Use a very sharp, paring knife to trace along the edge of the wax paper, getting as close to the cake as you possibly can.  After you have gone along the entire perimeter of the cake, slice down the edge of the wax paper ring and carefully pull it away.

Refrigerate the cake for at least one hour or up to six.  About one hour before you plan on serving, pull the cake out of the refrigerator so that the buttercream has a chance to soften. 

Enjoy! 

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LET'S BAKE TOGETHER!