Home » Blog » Recipes » Baking » Cupcakes and Cakes » Lego Cake, Fondant Brick Version
| | |

Lego Cake, Fondant Brick Version

*This post contains affiliate links to websites such as Walmart and Etsy. (As an Amazon Associate I earn from qualifying purchases.) By purchasing anything from these links, I may receive a commission at no extra cost to you. More information is available on my Disclosure page. I appreciate your support!

Thank you for Sharing!

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!


6 chocolate cupcakes on a chocolate cake

Fondant LEGO bricks

marshmallow fondant in red, yellow, blue, and green

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.

putting the marshmallow fondant in the molds

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.

marshmallow fondant lego block making in lots of colors

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

yellow marshmallow fondant lego blocks

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.

blue marshmallow fondant lego blocks

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

green, red, blue, yellow, and white fondant lego blocks
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!
Lego Cake with Lego Scene graphic

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

letter cookie cutters

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.

name out of marshmallow fondant

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*

sonic and mario cookie cutters made from a 3d printer
sonic the hedgehog in marshmallow fondant
super mario in red marshmallow fondant

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.

chocolate cake with chocolate cupcakes

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

6 chocolate cupcakes on a chocolate cake

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.

frosting on one of the chocolate cupcakes
blue frosting on a giant lego shaped cake

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?!

the word Lego on each cupcake, just like real legos

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

closeup of lego fondant border around cake

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

Lego cake, AFTER!

Fondant Legos surrounding a blue lego cake
giant lego cake with blue frosting, surrounded by smaller legos bordering it
Lego Cake

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

cake in the shape of a giant lego with smaller legos surrounding it
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!).

Giant Lego Birthday cake

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

Lego birthday party goodies
extra fondant lego pieces and sonic cupcake and super mario cupcake

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.

building block LEGO tablecloth

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.

gummy LEGOS candy

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!

Let me know if you make any of my cakes! I would love to see it! What other Lego Cake ideas have you seen that inspired you?

LEGO Cake with fondant lego border
LEGO Cake with fondant lego border with yellow background

Thank you for Sharing!

Similar Posts


Leave a Reply

Your email address will not be published. Required fields are marked *