How to make a Lego Cake
I have been wanting to make a lego-type cake for a very long time. I am not sure why I love Legos so much but I do. I used to have a Lego school set when I was little and I LOVED it. Even before getting this cake order I would research how to make a Lego cake. I always wondered. But I didn't have much luck finding any tutorials out there. So now...here we are!
Now there is the "cut out a lot of little nubs" approach, where after you cut your rectangle you individually place every little nub on top of it. Sorry, but this was NOT what I was willing to do. There was NO way I was going to make hundreds of itty bitty nubs to put on top of each Lego piece and in so many different colors. Not to mention it really wasn't going to look super neat... and that's always a big goal for me, a NEAT looking cake.
I needed a mold. Something where I would NOT have to cut out little nubs. Something that looked JUST like the building block pieces. I searched and searched but could not find a Lego mold that would work ANYWHERE! I even ordered one that turned out to be the size of big Lego ice cubes! (these are the big yellow and blue ones on Amazon). So if I wanted to get that perfect Lego-look this meant I had to make it myself!
So I did and now hand make these for anyone adventurous enough to take on this cake project:).
Now available on our website here.
Keep in mind this cake is all about prep work. If everything is well prepared, putting it together will be the fun part! So here we go with the materials and steps to make the building block cake.
For a cliff note description check out our youtube video:
Key Decorating Materials
Make your own or purchase from our shop HERE. To make your own use a lego piece and silicone (there are a variety available from SmoothOn.com). Secure block piece on glass with buttercream and with a cookie cutter around it. Work air bubbles out at each lego 'nub' with a large pin. Apply buttercream at edge of cookie cutter. Weigh and mix mold media, pour, let cure for required hours.
Make a name topper with fondant and a font printout / template (available on our website here and included with all mold purchases). Here is our tutorial on how to make a 2D topper. It is a Mickey topper but I use the same techniques! In sum, roll out your fondant to desired thickness, let dry for about 10 minutes, then, using pieces from your cut out template cut out each letter. With the cut out pieces stick them on the background pieces with shortening.
MMF in primary colors: Red, Yellow, Green, and Blue (but omg just imagine a pink, purple, and white block cake!! Sooo cute:)) You can make your own since there are various simple recipes online! Or use Wilton fondant in a pinch. Whatever you do, I DON'T recommend Satin Ice. This is a great fondant for many other purposes, however, for this project this fondant doesn't fill each cavity very well and lacks firmness to make neat-looking pieces.
NOTE: I love using homemade marshmallow fondant for any type of mold and cutout. This fondant has the right firmness, flexibility and texture to hold its molded shape and creates nice sharp cut outs (make sure you let it dry rolled out for about 10 minutes prior to cutting with a template). It is even better for such purposes when the MMF has sat for a day or two after making it (this increases firmness which is great for molds).
I used a 1/4 sheet cake (9"x13"). This gives you an extra block-y look.
Chocolate Ganache Your favorite ganache recipe will do, however you can also see gananche instructions on our post here.
Step 1. Prepare The Blocks (for the top only) - for a really sharp look prepare 2 days in advance.
- A couple of days before you want the finished cake make a number of block pieces for the top using the block mold and your different fondant colors.
- TIP: Firm MMF works best. Achieve 'firm' fondant by making and coloring your fondant at least 1 day before making these pieces. If your fondant is sticky try adding a dab of shortening or powdered sugar (avoid, corn starch, doesn't seem to work well with MMF).
NOTES ON HOW TO USE THE MOLD:
Roll about a 1" ball of fondant (roll it enough to get all of the creases out), then push the ball into the mold cavity real well with your fingers (not a roller). Then using a sharp knife cut off the excess on top so that it is flush with the mold. If this gets to be too sticky sometimes it helps to rub a little extra powdered sugar on top before cutting the excess fondant. Then just bend the mold back with your fingers and pull / peel the fondant piece out of the mold slowly (do not use anything else but your fingers so as not to damage the mold or your piece). Re-square the soft pieces with a knife or spatula on a large flat surface dusted with powdered sugar. You should be all set!
- I recommend starting with the lightest fondant color and working your way to the darkest (I would do yellow, green, red, then blue). This way you can keep from cross contaminating your fondant colors and save yourself from dry hands due to over washing. The reason you want to do this well in advance is to allow your pieces to dry and therefore create 'sharp' looking blocks. Drier fondant is sharper looking fondant and sharp looking fondant always looks cleaner and gives a more finished look. But if you are out of time last minute is OK too!!
- Next get a rough idea of how many pieces you need per color by estimating how many you will need to cover the top of your cake pan and cake board. (hint: try to envision how much fondant it will take to cover your pan)
- The size I used is a 1/4 sheet and for the look I wanted it required about:
- 50 green mold pieces
- 23 yellow mold pieces
- 13 blue mold pieces
- 13 red mold pieces
- Let the pieces dry for a full day or two (minimum overnight). You can save time by not fully drying but the pieces will have a softer look to them. Store them on your trays in a cabinet or drawers out of sunlight and bulb light to prevent them from fading or changing color.
- Notes on storage: DO NOT store them in an air-tight condition, this will cause fondant to sweat and stay soft, however, if drying out for about a week or so you can do this, however, I would test it. You might be able to store them in a paper box (anything but air-tight) but the lack of open air might affect integrity.
- Once they are fully dry cut the block pieces evenly into 3 smaller pieces. DO NOT cut all the green pieces since you need a good amount of those for the cake board.
- They are now ready!
Step 2. The Name Plate Topper
- While you blocks are drying and since you have just worked with all of your colors you can now use this fondant to make the name plate.
- Using a block font paper template, cut out the pieces for your name plate. Note: a copy of the letters I used for this project are now included in mold orders: For block mold including template click here. For the font template only click here. You can also create your own by downloading the font online.
- Roll out the fondant colors, cut out your template letters, cut the name, the black, yellow, and the red and black backgrounds using a small sharp knife. For a more thorough steps check out or How to make a 2D Topper Tutorial Here.
Step 3. The Cake
- Bake and cool your cake completely. Torte it by slicing down the center of the layer for the filling and then freeze. You can wrap or not (with plastic wrap or foil), this might depend on the types of other food items in your freezer. For instance I had a cake-only freezer so I never needed to wrap when storing short term. Short term freezing will incorporate more moisture into your cake so don't worry about it drying out:)! Short term might be less than 2 days (depending on your freezer). However, my home freezer I wouldn't use like this past 2 hours.
- When you are ready to start the decorating process pull the cake out of the freezer. Next separate the layers carefully and fill with your desired filling.
- Use your chocolate ganache to coat sides and top of cake with a spatula. If your ganache is too firm heat in the microwave for just a little bit and apply. Use a bench scrapper to achieve nice clean sides and top. Once your ganache is on if you want, to 'fix' the smoothness with the bench scrapper, heat a pot of water to dip and heat the bench scrapper.
- Refrigerate your ganached cake for about an hour to firm. While this is refrigerating let's start the side blocks!
4. Side Blocks
- Roll out wide pieces of 4 different colors preferably using a pasta roller. I use a kitchen-aid one that attaches to my mixer. Tip: To get a thicker piece than the #1 setting, reverse it (back the knob up). It will work just as well and give you a thicker piece.
- Let your the rolled out pieces dry preferably for about 1/2 hour to an hour.
- While these are drying, create your cutting guide. Using graph paper or engineering paper draw lines using a straight edge using the same width and length of your small molded block pieces (the dimensions of the final piece after you have cut it into 3). If you bought a mold these templates are now included with each block mold order!:) For Block Mold including templates click here.
- AFTER the pieces have firmed from the drying, cut out these pieces using a small knife, a straight edge, and your paper guide. By having waited for the pieces to dry out this will go a lot faster:).
- These I like to cut as I need them. I found these hard to estimate quantity.
5. Put it all Together!!
- Ok so this is what I think is the fun part! Apply a thin film of shortening to get your block pieces to stick. I like to use shortening because you can move your pieces around later if it needs tweaking.
- Next, start playing building blocks! Create your own block color pattern on top of the cake.
- Overhang the border blocks just a tad so the side pieces will meet flush just under them.
- Match the side pieces of the first row to the border pieces with the appropriate color.
- Cut side pieces where necessary
- Fill the remaining rows of the side freestyle!
- Apply green pieces on the board by using sugar glue. Simply make this with the following steps:
- 1 part tylose powder, 1 part granulated sugar and 4-5 parts super hot water
- Let sit for 15 minutes to set
- After it is all together cut the cake board to fit (so no cardboard is showing beyond the green board pieces) and place the name topper on the cake.
Whew, if you did all that CONGRATULATIONS!!
Funnest. Cake. ever. :-D
I know it is a TON of work but your little one (or big one) will LOVE it!
Funnest. Cake. ever. :-D
I know it is a TON of work but your little one (or big one) will LOVE it!
Happy Lego Cake Making!!