DIY: Geeky Birthday/Groom’s Cake

The time has come for another DIY post. And this month’s topic is… Cake! Whether you’re looking for a cake for your husband, sibling, kid, or parent… geeky cakes are a great way to go.

My husband has a summer birthday, so this time of year always brings out my creative baking side. I never realized that cake decorating could be so fun and artistic until the discovery of Pinterest and shows like Cake Boss. I figured I had to try it out for myself.

Starting out, I found this great blog post called “How Does She?” that gives step by step instructions on making DIY fondant for aspiring cake decorators. I would highly recommend checking it out!

What You’ll Need:


  • Cake mix (or make it from scratch if you’re feeling so inclined)
  • Round cake pans (I used 8″ and 9″ pans)
  • Knife or pizza cutter
  • Frosting
  • A couple bags of marshmallows
  • A bag or two of powdered sugar
  • Butter
  • Food coloring
  • Rolling pin
  • Chocolate chips and/or cocoa powder (for black or brown fondant)

Making the Fondant

Making fondant is fun and easy. During my first cake decorating escapades I followed the fondant recipe exactly, but I’ll admit that now I tend to use a more experimental method, throwing the ingredients together and adding more sugar or water to the mix until I get the consistency I’m looking for.

To make white fondant, start by microwaving marshmallows and a couple tablespoons of water in a glass bowl for thirty seconds at a time until they’re nice and melted. Coat a spoon and your counter with butter (sounds weird, but it prevents the marshmallow from sticking). Pour a couple cups of powdered sugar into your bowl and begin stirring. When the marshmallow blob begins to feel slightly less sticky, coat your counter with powdered sugar and spoon the whole mess out onto the counter. Adding more powdered sugar, continue to knead sugar into the ball until it’s no longer sticky but still soft. If you want the fondant to be colored, add food coloring (only a few drops at a time) and knead until you have the color you’re looking for.

Making chocolate fondant… And my super messy counter

To make brown or black fondant, I typically start by making chocolate fondant. Just throw some chocolate chips into the bowl when microwaving the marshmallows and add some cocoa powder in along with the powdered sugar. The resulting fondant is a rich brown color that can easily be darkened to black with  black food coloring.


Fondant can be made ahead of time and stored easily in the fridge. Cover the fondant ball in a layer of butter to prevent drying, wrap in plastic wrap and place in a container or plastic bag.

Prepping the Cake


For the cake, I cheat and typically use a boxed cake mix. For a single tiered cake, use one box of cake mix. For a two tiered cake, use at least two boxes of cake mix. For some added fun, food coloring can be added to white or yellow cake batter for a vibrant surprise. I typically bake my cakes a day or two ahead of time and freeze them (makes them more firm for decorating). Allow the cakes to cool and wrap in plastic wrap if you choose to bake them ahead of time and freeze.

When the time comes to assemble the cake, start by cutting a thin slice off the top of each cake layer. Usually cakes have a slight hump from rising during baking, so this assures you have a flat surface to work with. Stack the layers for each cake tier separately using frosting to hold them together (keep the tiers separate, you’ll stack them after decorating them). Cover the entire cake with a thin layer of frosting. This gives the fondant something to stick to.

Time to Decorate!


When using fondant, first cover your working surface with a thin layer of powdered sugar to prevent sticking. Grease your rolling pin with butter and roll the fondant into a thin layer (about an 1/8″ thick). If the fondant is a bit hard, stick it in the microwave for 20 or 30 seconds to soften. To cover the cake, carefully lift the sheet of fondant and drape over the cake. Press lightly to form it around the cake. Work slowly from the top of the cake to prevent wrinkles and tears. Excess fondant can be cut away using a knife or a pizza cutter.

Now comes the fun part-adding decoration! Fondant can be cut and formed into just about any shape, making it an intriguing medium to work with. With some added icing, you can come up with some amazing masterpieces!

Batman and Spiderman/Venom Cake

20140617_083304My husband loves comic books, so for my first attempt at cake decorating I decided to try a superhero/villain themed cake. For my Batman and Spiderman/Venom Cake, I started by decorating the bottom tier in half black and half red fondant. A rich red color is difficult to achieve with food coloring, so I did end up painting food coloring directly on the cake surface to deepen the color from pink to true red. Then I formed a spider shape from excess fondant and attached it to the cake using just a little bit of water. I added spider webs to the cake using strings of white fondant.

The batman tier was draped in black fondant. I cut an oval of yellow fondant and plopped it right on the top. The bat was cut freehand using a butter knife and attached to the cake with a little water. With the done, I plopped the top tier onto the center of the bottom tier. To hide the rough bottom edges of cake, I cut squares of yellow fondant and created a batman utility belt to go around the bottom of the top tier.

Batman and Spiderman/Venom Cake 2014

Magic the Gathering Cake

Since I was pretty proud of my first major cake attempt, I decided to try it again for my husband’s next birthday. He enjoys playing Magic, so I figured I’d try a MTG themed cake. I didn’t have much time, so this cake was bit simpler, using chocolate fondant as the base and chocolate frosting piped around the cake edges. On the top of the cake, I cut freehand copies of the major land symbols from the card game (forest, swamp, mountain, island, plains) and attached them using a bit of water. Then I added highlights using a little white icing.

Magic the Gathering Cake 2015

Overall, pretty proud of the results! Happy baking 🙂



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