How to Make a Lego Cake

April 28, 2010

Lego How-To

Lego fanatics, enthusiasts, hobbyists, or people who just can’t get over their love for the plastic bricks: get ready to eat your Lego! No, Lego is not going to release edible Lego bricks but you can! Lego cakes have been the staple party food for Lego-loving kid parties.

However, if you love the idea of a Lego cake, you don’t have to gate crash ¬†your neighbor’s children’s party. You can make your own Lego cake with your everyday cake ingredients. Betty Crocker’s recipe for the Lego cake is one of the easiest to follow and using ingredients you can find right in your kitchen.

Photo Courtesy of Chocmocake's Flckr Photo Stream

Difficulty: Easy
Things you’ll need:

1 Betty Crocker cake mix,


vegetable oil,

2 containers of Betty Crocker Rich and Creamy Vanilla frosting,

yellow, blue, and red food coloring,

a tray,

12 marshmallows, cut crosswise.
Step 1

Following the cake mix instructions, mix it with the water, vegetable oil, and eggs, and pour it into a greased baking pan. Afterwards, put the pan in your preheated oven to make your basic cake.
Step 2

While the cake mix is in the oven, prepare your frosting. This will serve as the Lego cake’s paint. Since the recipe calls for three colors, prepare small bowls for each color that will be made. Prepare a cup of red frosting, 1 cup for yellow, and 2/3 cup of blue. Leave some frosting uncolored for later.
Step 3

Take out the cake mix from the oven, and let it cool. Cut the top to make it flat, and cut the whole thing into thirds. Cut the last third in half to make it square. You now have blocks for your Lego.
Step 4

Frost your blocks with one color per block. To make the ‘pegs’ and attaching them on your cake, take the halved-marshmallows and frost it. Attach them on top of your frosted blocks with toothpicks and making sure it’s the same color as the blocks they are on. Use six for the rectangular pieces, and 4 for the square. Congratulations on your Lego cake!


  1. Dan Punch
    July 16, 2010

    It’s interesting that your recipe calls for frosting when the corners of the lego blocks show seams…fondant seams. Also, where on earth were you able to find marshmallows that size?

  2. Anne
    July 16, 2010

    Ask Betty Crocker

  3. toh246
    July 18, 2010

    I agree with Dan. The cake in the photo is not for the recipe attached. The seams on the cake are fondant, and this cake required more than the amounts for the recipe above as well. Not to menmtion that a “cake mix” density would be too light, and not hold up to the weight of layering. You can visualize the size of the cake if you look at it, from the perspective of the sink adjacent to it. This cake was also done by someone with great expertise – the execution of the fondant is excellent, and I’m sure the layers have also been supported with dowels. The size of the circles is probably that of a ring ding, and was covered individually. Being a pastry chef, and having just finished a Lego cake myself, I can assure you that the difficulty level on this one is “high”, and kudos to the actual creator of the cake in the photo – it’s certainly not the person who posted this recipe. To them, shame on you!!!

  4. Kerri
    August 9, 2010

    Not to mention you can not get that true red colour and produce something edible simply by using basic food colouring!!!!!!

  5. Lori
    September 1, 2010

    what do you think of covering pound cakes with fondant? would they be dense enough to hold the layers? I love the idea of this cake, but was also confused by the directions. Definitely not the same as the photos shows. I have found HUGE marshmellows (called Giant Roasters Campfire Marshmellows) at the store and find that an intriguing idea for the circles.

  6. Ralph
    September 1, 2010

    We are not very accurate when it comes to recipes since this is a Lego blog. This was an article suggestion by a fan and he gave us the recipe. I have no idea on how to make fondant and if it is going to be good on pound cakes, I just love eating cake :) I think it would be great if you guys can give us a great recipe to feature on this blog and maybe you can make a better Lego cake version. I do know however that there are Giant marshmallows as mentioned by Lori.
    Ralph´s last [type] ..Segundina Salucop- A Tribute To A Nurse- A Mother- Wife and Friend

  7. Ande
    October 31, 2010

    I am searching for a lego cake design to use for my son’s birthday. I am going to use mmf and a design similar to this. This cake is def. huge and way more than one cake mix. Love the design though so I am going to try to recreate it the best that I can….wish me luck!!

  8. Joe
    October 31, 2010

    Best of luck with this. We would love to see the finished cake!

  9. Ralph
    October 31, 2010

    Yes a photo of the Lego cake sent to us would be greatly appreciated…
    Ralph´s last [type] ..Getting To Know CWN

  10. rose
    November 30, 2010

    I have found marshamallows that size at Walmart. Thanks for the instructions. Because of the pictures I can create something that looks like lego blocks.

  11. Jaheed
    December 1, 2010

    This is a great article although I am not a baker…I just love cake and Lego!

  12. Jamie
    February 6, 2011

    I loved this cake and had to try it out…My friends son just turned four and is constantly playing with Legos. I am not a fondant person so I just used a butter cream icing and two 9×13 cakes (I made the cakes from scratch)Regular jumbo marshmellows and just cut about a cm off of the bottom and then borrowed some lego guys from my friends son and it was a huge hit…I can’t find anywhere to upload a photo of it so if someone could fill me in I would be happy to share with you my version of a lego cake Cheers :)

  13. Ralph
    February 7, 2011

    Hello Jamie! Thanks for the comment. I will send you a message shortly.
    Ralph´s last [type] ..Getting To Know CWN

  14. April
    June 29, 2011

    I’m about to try this cake (well one similar) for my son’s party. I ended up buying a large roast pan to bake the cake in, versus a regular 11×9 pan. I also bought a small 4″ round cake pan to make the “bumps” out of. The marshmallow is a good idea as well. And for those questioning fondant…I was looking into using it for this cake (tried it last year for a Krabby Patty cake), but read about the “paper towel method” and decided to try that with regular icing. Tastes better but still looks as good. Can’t wait to test out this cake!

  15. Stephanie
    September 28, 2011

    You can buy Jumbo size marshmallows now and they are the perfect size for the pegs. This is definetly a fondant cake. But if you know how to make a good buttercream icing, it is great for frosting. You can get smooth lines like fondant (though not as perfect) by getting your spatula (metal of course) warm. I keep a pyrex nearby with hot water and keep the spatula in it while not using it. Make sure you wipe off the spatula so you don’t have driping frosting everywhere.

  16. Stephanie
    September 28, 2011

    One more hint, make sure your cake is frozen. Also, marshmallow fondant is easier and tastier than regular fondant which requires a great deal of skill.

  17. karen
    October 13, 2011

    I made this Lego Ninjago spinning cake that actually spins see the youtube clip, I took me about 6hours!

  18. Ralph
    November 10, 2011

    amazing cake!!!! we love it.

  19. Angel
    January 6, 2012

    My son is about to be 10 this month and I am going to try this reciepe; but, with a few tweeks. I will post picks after the 22nd.

  20. Crystal
    March 2, 2012

    I make cakes all the time, layered and covered in fondant, and I only use regular cake mix. Works fine and is stable enough. I wish the method used to make the cakes in the picture was posted – the pictures should definitely match the recipe!

  21. Adriana
    September 17, 2012

    I need to make a lego cake and would love to have the original recipe that it is on the picture,..

  22. Lisa
    November 9, 2012

    when i make cakes using fondant i ice the cakes with a thin layer of icing first, it’s called a “crumb coating” it not only helps manage the crumbs it helps the fondant stick. i think they just left out a few steps

  23. Leanne
    November 2, 2013

    You can find the frosting version picture, full recipe and video here: it looks great.

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