Lego Cake, Fondant Brick Version

Liberty Brammer
by Liberty Brammer
1 Cake
2 hr 45 min

If you’ve ever looked online for Lego Cake ideas, you know there are some really great ideas out there! For my son’s 7th birthday, I wanted to make him a fabulous Lego themed birthday cake. Whenever I am getting ready to make a birthday cake, I usually have already been searching Pinterest for ideas. I save my favorite finds, and then make a plan in my head of how I am going to use those ideas to create a one-of-a-kind cake. This time, it was no different. I found a lot of great Lego ideas on Pinterest, not just for Lego cake ideas, but for a Lego themed birthday party, too!

First: Make Fondant LEGO bricks

This Lego Cake was my first adventure with fondant. I am not a fan of cakes made with fondant, but I didn’t know how else to make lego bricks. I found a fondant recipe that used marshmallows, and so this fondant was pretty easy to make and also tasted okay (if you think marshmallows mixed with powdered sugar tastes good, then you will love this fondant)! So how do you make a fondant Lego cake? I will tell you! First, I ordered some authentic sized Lego brick molds from Etsy allowing time for shipping. I did not want larger molds that were not the true size of the regular Lego bricks. So I made sure to get the right size Lego mold.I made four different colors of marshmallow fondant. You can make as many colors as you like.

I found that it was easier to get the fondant out of the molds by putting them in the freezer for a minute or two. I carefully laid out plastic wrap to set the fondant Legos on, so they wouldn’t stick. The texture reminded me of gum, so if it was warmer it was softer and sort of sticky like gum.

I then covered the fondant Lego bricks with plastic wrap so they wouldn’t dry out.

The little edible Legos were so cute! They were a lot of fun to make even though it was time consuming.

Tip: Make the fondant bricks at least a day ahead of time and assemble the entire cake on a different day.

After I decorated the Lego cake, I placed the extra fondant Legos on an actual Lego baseplate as a “plate” to serve them.

Fondant Legos

Fondant Legos in Review:

  1. *** Order Etsy LEGO mold ahead of time*** to allow for shipping
  2. Make marshmallow fondant in several colors (wrap in plastic wrap until ready to use)
  3. Press fondant into LEGO molds
  4. Freeze for a minute or two
  5. Bend flexible mold to get the bricks out
  6. Lay finished bricks on plastic wrap
  7. Cover finished bricks with plastic wrap and store at room temperature until ready to use.
  8. Decorate cake as you wish using finished LEGOS!

I already had letter cookie cutters, which I used to help me make my son’s name in fondant.

Next, I cut off the corners of the blue letters so they would look like the Lego font. Then I laid them on a piece of red fondant and cut around the red fondant for a layered look to further imitate the Lego font. Later I added a yellow layer underneath the red fondant to complete the look.

Because my son also loves Sonic the Hedgehog and Super Mario, I had ordered cookie cutters from Etsy. I used them to cut out fondant cupcake toppers. Sonic the Hedgehog Cookie Cutter* Super Mario Cookie Cutter*

How do you make a Lego Cake?

I’m glad you asked! I started by baking a chocolate cake and cupcakes, because my son loves chocolate. You can use any flavor cake mix that you prefer.

I placed the cupcakes on top of the cake to see how they fit. Then I took off the cupcake liners, and cut off some of the bottom of the cupcakes so that they were not too tall.

Lego Cake, Before

Then I frosted them. I tried a different frosting recipe this time and didn’t like how it turned out. The frosting recipe that I recommend that you use instead is this one:

  • 1 lb. butter
  • 8 oz. cream cheese
  • 21 oz powdered sugar (approximately)
  • 1 TBLSP vanilla
  • 1 TBLSP milk

I sprinkled coarse sugar sprinkles onto the frosting, and then piped the word “LEGO” onto each cupcake to imitate real legos. Did you know real legos have the word “LEGO” printed on each of those tiny dots?!

Then I used my marshmallow fondant Legos as a border around the edge of the cake, alternating the colors in a random fashion.

I hoped that my son would like his cake as much as I did!!

Lego cake, AFTER!

Lego Cake

All that was left was to add his name to the cake, along with some candles.

Giant Lego Cake

Choose based on your Skill Level.

There are a lot of options to choose from when you are looking for Lego cake ideas. I chose a combination of ideas that matched my skill level in cake making. For example, I didn’t think I could make an entire cake out of fondant Legos and have it look nice. That is why I made most of the cake like a regular cake with frosting, and then added the fondant Lego border. Although, after making these fondant Legos, my confidence has grown and maybe I would be brave enough to try an entire fondant cake next time. I would recommend the same method for you, too. Choose the kind of cake that matches your skill level so that you will not be overwhelmed when making it (or worse– have a “Pinterest Fail” kind of cake!).

The cake table offered choices of cake, cupcakes, and extra fondant LEGOS.

On another table I had the rest of the party food. Did you know that the Dollar Tree has lots of Lego themed partyware like napkins, paper plates, and disposable table cloths? They are not brand named Lego themed, so they look a little different and are just called “building blocks.” They even have a “Happy Birthday” banner! Since my cake and cupcakes were busy enough, I did not think the building blocks tablecloth would look right so I just used it on the other table.

By the way, guess what I found at the Dollar General (not the Dollar Tree) in the candy section??? GUMMY LEGOS!!! Again, not brand name so not exactly the right shape, but gummy building blocks indeed! They were a popular item at the party, let me tell you.

Other Lego Cake Ideas

If you are wondering whether you want to make a Lego cake or not, let me suggest some alternative ideas. You may remember that I like to use toys for cake toppers sometimes, and my kids love it. Why not use a large LEGO baseplate, set it right on top of the frosted cake, and then set a new boxed LEGO set on top of the base plate? Or build something on top of the base plate, like your child’s name, or the number they are turning. For example, take this number idea and instead of hanging it, lay it flat on top of your cake. I hope that you have enjoyed seeing how I made this Lego Birthday Cake recipe. *** Be sure to check out some of my other Cakes, too! *** icon

Lego Cake, Fondant Brick Version
Recipe details
  • 1  Cake
  • Prep time: 2 Hours Cook time: 45 Minutes Total time: 2 hr 45 min
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  • 2 cake mixes
  • Ingredients to make mixes: usually eggs, oil, and water

Make one cake mix in a 9x13 pan.
Make one cake mix into cupcakes.
Assemble as described in post.
Liberty Brammer
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