As the girlfriend of a major computer/video game geek, and a fan of portal myself, I decided to make the dear boyfriend this weighted companion cube cake for his birthday.

Note: This cake can be made with very little experience with fondant. But, I couldn't find any other way to make it without fondant, so you gotta use fondant.

Think I've said fondant enough?


Step 1: Making the Base

I used 2 8-inch square cake pans, and betty crocker's yellow cake mix for this cake. Just cool them until they're completely room temperature ((any heat will melt the frosting))

Aqua's Frosting Recipe?
3 Cups powdered sugar
3 tablespoons of butter.
4-5 tablespoons of COLD milk.
Mix well, add more or less milk as need be!

Frost the top of both cakes, and layer them on top of each other. Pretty easy, right? I thought so too.

Then frost along the sides as well. All this frosting will help the fondant stay in place, as well as give it a more pleasant flavor.

It doesn't have to be perfect, as it wont be what is showing.

You can add colors and/or flavors to your frosting as well. For this cake I recommend pink, as it will probably save you a step or two later!

Be sure to save some of the frosting for later, you'll need it!

This was requested by my son, for his 15th Birthday. Thank-you so much for this instructable! (My first forage into making fondant was fairly successful)
A Companion Cube cake a made for a friends birthday =)
YOU ARE AWESOME!! Thank you so much for posting this. Will be baking for my husbands birthday in a week :)
OMGOMGOMGOMGOMG!!!!!!!!!<br><br>THECAKEISALIETHECAKEISALIETHECAKEISALIETHECAKEISALIETHECAKEISALIETHECAKEISALIE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!<br><br>no one ever gets me because, bec-c-c-cause.........<br><br>.....I'm different.
please tell me we don't have to throw it in the incinerator!
does an oven count as an incinerator?
1. Dosent look like a cube<br>2. this is a insult to the companion cube, you killed it.<br>3. Nice cake :D i want sum <br><br>but seriosly, your moking its death, the cake is a lie
i know i've seen that cube somewhere before...
Portal! (video game)<br>
Ive found that an easy way to cut fondant is with a rotary cutter (i.e. a pizza cutter)
<p>A good friend of mine and I decided to try making this cake for a birthdayparty we were invited to. We all got to know eachother at a university summerschool in game developing so I guess we all qualify as geeks.<br /> Anyway we were all very satisfied with how the cake&nbsp;turned out, so I just wanted to thank you for the instructable!<br /> In case anyone is wondering,&nbsp;we added some goo's from &quot;World of Goo&quot; to the cake, also made out of fondant, call it blasphemy!<br /> Btw. we used a recipe for making our own fondant, mainly based on marshmallows, it was great fun :P</p>
awesome idea with the goos, physics based games belong with other physics based games also world of goo and portal were both just amazing games
the cake is still a lie to me 0_o
Hmmm.... putting the cube in the oven looks oddly familiar...*sob* no! never again! I&nbsp;will not burn&nbsp;my pal&nbsp;again!!!
My roommate and I are both huge portal fans.&nbsp; I think I'll make this for his birthday (with a little help from his wife).
This was a triumph.<br /> I'm making a note here: HUGE SUCCESS.<br /> It's hard to overstate my satisfaction.<br /> <br /> Aperture Science:<br /> We do what we must because we can.<br /> For the good of all of us<br /> Except the ones who are dead.<br /> <br /> (Chorus 1)<br /> But there's no sense crying over every mistake<br /> You just keep on trying till you run out of cake<br /> And the science gets done and you make a neat gun<br /> For the people who are still alive.<br /> <br /> I'm not even angry.<br /> I'm being so sincere right now.<br /> Even though you broke my heart and killed me.<br /> And tore me to pieces.<br /> And threw every piece into a fire.<br /> As they burned it hurt because<br /> I was so happy for you.<br /> <br /> (Chorus 2)<br /> Now these points of data make a beautiful line<br /> And we're out of beta we're releasing on time.<br /> So I'm GLaD I got burned think of all the things we learned<br /> For the people who are still alive.<br /> <br /> Go ahead and leave me.<br /> I think I prefer to stay inside.<br /> Maybe you'll find someone else to help you.<br /> Maybe Black Mesa -<br /> THAT WAS A JOKE. HA HA, FAT CHANCE.<br /> Anyway, this cake is great:<br /> It's so delicious and moist.<br /> <br /> (Chorus 3)<br /> Look at me still talking when there's science to do.<br /> When I look out there it makes me GLaD I'm not you.<br /> I've experiments to run there is research to be done<br /> On the people who are still alive<br /> <br /> And believe me I am still alive.<br /> I'm doing science and I'm still alive.<br /> I feel FANTASTIC and I'm still alive.<br /> While you're dying I'll be still alive.<br /> And when you're dead I will be still alive.<br /> <br /> Still alive<br /> Still alive
The companion cube cake ISNT&nbsp;a lie
GlaDoS:the enrichment center would like to inform you that the weighted companion cube cannot speak...in the event that the weighted companion cube does speak the enrichment center strongly advises you disregard its advice
Bleck Fondant. I Made a companion cube cake last year, 3 layers and the corners on the sides of the cube were made of cake. Took awhile to get them to stay, but frosting and toothpicks works.
Make a life sized: GlaDOS, Chell, and working Portal Gun that doubles as a cake.
you should make the whole cube next time! mmmmmmmmmmm cake!
lol i just bought my bf a companion cube poster, too bad his bday passed. I would reccomend trimming the actual cake so it is flatter. it just looks a little round at the top
That's a whole lot of sugar. Sugar!
This is brilliant! After making one of the other Portal cakes on this site, I couldn't help but look for a companion cube cake, and here it is! Five stars!
does the fondant actually taste nice? I mean not while having small bits of it while making it but large pieces while eating a slice of cake cos i know icing can become quite sickening after eating alot of it
Amazing! Thank you!

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