This Lego cake design is so very simple! No special tools or cake decorating skills necessary!
I posted this Lego Cake on Instagram a few weeks ago for my son’s 4th birthday party. Not too long after that my Facebook feed and inbox started filling up with requests of how to make this design at home. Honestly I wasn’t even going to post this and I just took a few sloppy pictures- I hope you don’t mind me sharing!
Apparently there are other little boys who like Legos. Who knew? They are kind of a big deal I guess. Now you can take this design and run with it. I tried with all my heart to get my son to pick a different frosting color but he insisted on red. So red it was. Wow was it ever!
This is technically a 3 layer cake. I used box mixes. Feel free to use a homemade cake made with the tears of unicorns if you wish. The bottom 2 layers are 9×13 yellow cake. The 3rd 9×13 cake was chocolate and I simply used a biscuit cutter to cut out 6 rounds. I placed them all on top with a dab of frosting. Then I did something crazy and heated my buttercream up to a pourable consistency. In theory this would have worked well if I hadn’t have stopped to snap a quick picture. Don’t do that. Just keep pouring. The frosting hardens quickly.
Or just frost it with a spatula like most normal people do. Whatevs.
A lot of you asked about the little Lego head pops too so be sure to see my full post and Marshmallow Lego Pop video tutorial here.
39 Comments on “Lego Cake”
I LOVE IT!!! the easiest one i have found so far! i am not a baker and this looks very sinple to do! i would do it half the size though. 3 layers of 9×13 is too much cake for 3-4 years old LOL thank you so much for sharing! the heating technique is genious
Can i use stevia in place of the Erythritol and if so how much? Thanks.
Hi, it looks amazing, and I am going to make it then on Saturday! How long does it take you to make it? For Saturday party, I only have a few hours on Friday to make, and I am a bit amateur in baking. As the party boy is at home with me, and he shouldn’t know about this. I have to come to another house to make…
Your tip will help me in planning. thanks~
Cracking up about the tears of a unicorn comment! You are my kind of mom. I’m going to try the heated icing trick. I’m also going to try Mallowmars as the top knobs.
Cracking up…tears of a unicorn! You are my kind of mom!
How did you get the sides so smooth and edges sharp? Thanks!!
This looks so delicious and you make the picture look so great. Thank you so much for sharing
Love this! I’m going to make it Saturday!!! Looks like you frosted with vanilla frosting first, then poured the colored, heated buttercream over?
I have the same question as Sally: What is the best way to move the cake to a clean surface after you frost it? I’m making one of these for my son’s 6th birthday in April. Thanks!
Hi Katrina, I love your cake! I just wanted to make sure I got the recipe right. Do you stack the two 9×13 cakes on top of each other and then cover them with frosting? You can’t tell from the picture, it just looks like one thick cake. Thanks so much!
How do you move the cake off the pouring surface? i want to try this but i am afraid of the puddle underneath and how to move the cake to a clean area after pouring. any tips tricks?
So just wondering what the white frosting was on the cake before you put the red on? I really want to make this cake for my sons birthday. I love the glaze look to the frosting. Do you think that if I got store bought frosting and colored it and then heated it up it would do the same as your homemade?
I used a basic homemade buttercream frosting. I haven’t tried it with store bought. You could also just frost the cake as you normally would then use a warm knife to smooth out the frosting. Just keep dipping the knife in hot water then wipe dry before you smooth the frosting down. Good luck!
This is such a great idea! Did u add food coloring to the butter cream frosting while heating it to make it red?
Yes I added the red before I heated it. Thank you for stopping by!
I told my daughter-law about this cake, and my grandson love it.
I just frosted my lego cake, but used a butter based buttercream. Yikes, I am scraping off the frosting and going to buy shortening and cream to make your frosting. How hot do I need to get it?
LOVE this cake and even more I love your comment about making a homemade cake with the tears of unicorns. Classic!
I cut marshmallows in half for the round pieces on top!!
Awesome idea! I think my cake was too large for that because that was my original thought but I needed larger rounds. Maybe if I had gotten those gigantic ones?! lol
I wish I’d seen this cake when my boys were little. They loved legos and would play with them for hours. What a great idea for a cake! Thanks for sharing your photos.
Thank you Shari! Boys sure do love Legos, right?!
What brand of frosting did you use or is it homemade?
I use homemade buttercream. You can find my recipe here: https://www.inkatrinaskitchen.com/2011/04/cookie-monster-cookies.html but a canned frosting would work just as well for this.
I make my own buttercream icing too but how did you get your red so vibrant? Mine always just turns out pink/light red when I add red dye (either liquid or gel) to my white icing.
I threw a lego themed party for Trevor last year and made cupcakes with candy lego bricks on top. I love your cake!!
Awesome idea, Amy! I couldn’t find those candy Lego bricks… I’m too much of a last minute planner to have ordered them online lol
so neat, love you poured the frosting to make it more smooth! we have HUGE lego fans here.
I loved it too… until I stopped to take a picture! Ha! But it all worked out in the end.
Thank you so much!
aww this is so cute
Thank you! So glad that you liked the cake.
As a dad of two lego-loving boys, I would be a hero if I made this! I love how you got the lego writing down perfectly. So cool!
I am just about the worst cake decorator in the history of EVER, so thank you! 🙂
What a cute cake!
Thank you! This was a fun cake to make.
How cute! I love the heating trick, that would work for lots of things. Great idea!
Thanks! That is one of my favorite cake tricks because I am the worst cake decorator!!