How to Make a Portal Cake




Introduction: How to Make a Portal Cake

How to make a cake that looks like the cake from the ending of Portal, the video game.  This one is edible and without the less than tasty stuff like fish shaped solid waste in the original recipe.  this is a big cake. i cut mine into 9 slices to preserve the appearance  and that was WAY too much cake for one person to eat. 

Step 1: Get Your Stuff Together!

 you'll need:
1 round 8 X 3 inch pan. i got mine at Michaels craft store. the brand is "Celebrate It"
1 can of cake release spray. i like pam for baking. 
a mixer because doing this all by hand would just suck.
2 boxes of your choice of cake mix and whatever is required to make said mix into batter. i used Pilsbury Funfetti.
9 glossy red gumballs
1 white larger than average candle. I used a left over Hannukah candle. 
enough chocolate curls to cover. i used a dark belgian chocolate block and made curls/shreds by hand. this made a huge mess and took forever. if you can find pre done chocolate curls, use them. I used a cheese plane.
wire cooling rack
bamboo skewers for checking doneness 
large bread knife or cake leveler.
frosting bag and round tip, wilton #8. 

Buttercream frosting:
2/3 c soften butter
4 c powdered sugar
1 tsp vanilla 
4 Tbs cream
5 Tbs cocoa powder

Raspberry cake filling:
1 1/2 c frozen raspberries
1 Tbs cornstarch
2 Tbs lemon juice (you can pretend it's combustible lemon juice if you like) 
1/4 c sugar

Step 2: Start the Cakes

Pre heat oven according to the instructions on the box of mix. Spray your pan liberally with the baking spray. you do NOT want this sticking to the pan. 

make a box of the mix into batter using the instructions on the box. dump the entire bowl of batter into the cake pan. Bake according to directions but add on about 10 minutes to the bake to compensate for the thickness of the cake. because your oven will vary, you'll just have to watch it and check it till it's completely done in the middle. when done, place the cooling rack on top of the cake in the pan, invert all of it leaving the cake on the cooling rack, hopefully free of the pan.

while your oven is reaching temp again, wash your pan, re spray it with baking spray and make up the other box of cake mix. make the other cake the same way you made the first.  


when cool, level out the cakes using a knife or cake leveler.

Step 3: Make Cake Filling

Make raspberry cake filling. don't like raspberry? you can skip this step and make and use a little extra frosting. i like the raspberry filling because it's a little tart and is nice against the sweet frosting. 

Combine all the ingredients in a med sauce pan over med- high heat, stirring occasionally till boiling. switch heat to medium and stri constantly till everything is dissolved. you'll see the raspberries break up completely and it'll change color to a dark, deep red.  let cool completely. don't try to taste it till it's cool, this stuff is like molten lava for your mouth. LFMF.

Step 4: Make Buttercream Frosting.

Canned frosting sucks. Making your own buttercream frosting isn't as hard as it seems and the rewards are great. 

let 2/3 c of butter soften on the counter. don't try to microwave it. you'll end up with melted butter and that isn't what you want. 
beat the butter with your mixer till light and fluffy. Gradually add in powdered sugar beating well between each add in. beat in vanilla and cream. beat till it's the right consistency . 

Now is the time to save off some of the white icing for the dollops that adorn the top of the cake under the gum balls and  candle. put it in your assembled icing bag to keep the air off it. I saved off like 1/2 a cup worth. 

Now beat in your 5 Tbs of cocoa powder, slowly adding it in like you did the powdered sugar. beat well, and cover.

reward any mantis men helping you at this time with a frosting beater or spoon to lick ;)

Step 5: Assembly!

Put one of the cake rounds carefully down on whatever plate you are using. the flatter the better. a piece of tinfoil wrapped thick cardboard would be marvy. under the edge of the round, slip pieces of parchment paper, wax paper, or tinfoil. 

On top of the round, slather on a good amount of the raspberry filling going all the way to the edges (or use the extra frosting you made). 
Place other cake on top of the other. make sure it's seated well and lined up properly with the other.

Use your chocolate buttercream frosting to frost the staked cakes with a nice thick layer of frosting making sure all the cake is covered.
now apply your chocolate shavings and curls to the outside of the cake. i used my hand filled with shavings to press them gently into the frosted cake sides. a spoon filled with shavings works well too but takes longer. make sure you cover the entire cake completely.

when you're cake is covered in shavings, remove the excess around the cake, pull out the paper pieces or tin foil you put under the edge of the bottom cake round. then remove what little excess is left. 

Step 6: Decorate!

Using your saved white frosting in your tipped bag, place circles of frosting evenly around the top of the cake. place your red gum balls in the center of each delicious frosting spot. put a small amount of frosting in the center of the cake and stick your candle in the middle of the frosting. light and sing the Portal song because this was indeed a triumph! 

serve to all your fellow test subjects. wrap any left overs tightly as buttercream tends to pick up odd flavors in the fridge. the cake can be refrigerated or left out but buttercream can get a bit melty if the room temp goes too high.  

1 Person Made This Project!


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Reply 6 years ago

*face palms*


Reply 10 years ago on Introduction

hrmm...nope. the original recipe doesn't call for strawberries.
original recipe:
1 18.25 ounce package chocolate cake mix.
1 can prepared coconut pecan frosting.
3/4 cup vegetable oil.
4 large eggs.
1 cup semi-sweet chocolate chips.
3/4 cups butter or margarine.
1&2/3 cups granulated sugar.
2 cups all purpose flour.
Don't forget garnishes such as:
Fish shaped crackers.
Fish shaped candies.
Fish shaped solid waste,
Fish shaped dirt.
Fish shaped ethyl benzene.
Pull and peel licorice..
Fish shaped volatile organic compounds
and sediment shaped sediment.
Candy coated peanut butter pieces, Shaped like fish.
1 cup lemon juice.
Alpha resins.
Unsaturated polyester resin.
Fiberglass surface resins.
And volatile malted milk impoundments.
9 large egg yolks.
12 medium geosynthetic membranes.
1 cup granulated sugar.
An entry called 'how to kill someone with your bare hands'.
2 cups rhubarb, sliced.
2/3 cups granulated rhubarb.
1 tablespoon all-purpose rhubarb.
1 teaspoon grated orange rhubarb.
3 tablespoons rhubarb, on fire.
1 large rhubarb.
1 cross borehole electro-magnetic imaging rhubarb.
2 tablespoons rhubarb juice.
Adjustable aluminum head positioner.
Slaughter electric needle injector.
Cordless electric needle injector.
Injector needle driver.
Injector needle gun.
Cranial caps.
And it contains proven preservatives, deep penetration agents, and gas and odor
control chemicals. That will deodorize and preserve putrid tissue.


Reply 10 years ago on Introduction

dunno why i saw strawberries, after looking up the cake online.. mebe they suited it betterer


Reply 10 years ago on Introduction

strawberries would certainly be tastier. cherry gum balls are kinda gross imo. the portal signs show cherries on the cake, but maraschino cherries, candied cherries, or even fresh cherries just didn't look right when compared to the cake in the game.


Reply 10 years ago on Introduction

I wonder why they need an adjustable aluminum head positioner 0_0 ;). What does that have to do with the cake, the recipe doesn't call for a head :).


Reply 10 years ago on Introduction

I would have thought more along the lines of glacé cherries...


10 years ago on Introduction

I've just made this cake today for my birthday and it was awesome. Especially the icing added something. I did use cherries instead of gumballs as filling and on the top. Really good recipe!


Reply 10 years ago on Step 2

fruitcake is ALWAYS a lie. blech! it is neither really fruit nor cake but rather a indigestible brick best used for keep doors stopped open or given to people to hate as a gift.


Reply 10 years ago on Introduction

See: "Junie B Jones and the Yucky Blucky Fruit Cake."
Also, I agree.
Also Also,
That cake is a triumph!