How to make the Fallout Jello Cake

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If you were as impressed as I was with the towering Jello Cake extravaganza in the Fallout series, then look no further for step-by-step instructions for creating your own Fallout Jello Cake masterpiece.

Hint: This also makes a great fourth of July dessert!

I love Jello, especially molded Jello that looks like gelatinous bundt cakes, so it wasn’t a hard decision to want to re-create the Jello Cake from Fallout.  Was it a challenge? Yes. Was it a success? Maybe. Do I have any regrets? No.

Get ready to roll up your sleeves, and prepare for some serious fails (because they most likely will happen) as we dive right into making this epic Jello beast of a cake.

Why you’ll love this recipe:

If you manage to pull it off the first time, you will be overjoyed with triumphant success. Go ahead and pat yourself on the back—job well done.

If you failed monumentally, you can still look back at all the fun times you had yelling at the red Jello as it slowly slid off the top and into Oblivion. Or the dirty looks you gave the blue Jello that refused to release its grip from the mold. And let’s not forget the foul-mouthed lecture you imparted on the cake as it caved in on itself. You see! It WAS fun and you DID love it!

Fallout Jello Cake Outline:

This is going to be a scaled-down version of the Jello Cake in the show because we aren’t feeding an entire vault (plus raiders).

1. Base: An 11” x 15” sheet cake, frosted.
2. Middle: An 8.5” blue Jello ring mold.
3. Top: A 6” red Jello tower mold.
4. Decoration: A mix of red and blue Jello squares, as well as whipped cream piped around the Jello.

Ingredients you need for the Fallout Jello Cake:

• Box Cake Mix. Yes, you could make this from scratch…but you also have Jello to juggle. Do yourself a favor and just use the box mix. You’ll need two boxes to fill the 11” x 15” pan.
• Red Jello. This can be Cherry, Raspberry, or Strawberry which will yield the brightest red color. You will need six 3 oz. boxes to fill the 6-cup mold, plus one extra box for the Jello squares on top.
• Blue Jello. Berry Blue is pretty much the only option if you are using the Jell-O brand. You will need four 3 oz. boxes to fill the Tupperware ring mold.
• Heavy Whipping Cream. For the whipped cream and frosting.
• Powdered Sugar. For the whipped cream and frosting.
• Unsalted Butter. Softened to room temperature.
• Salt. Just in case your frosting is too sweet.
• Yellow Food Coloring. This is for the piped edge around the cake base.

Special Tools you will need:

• An 8.5” Jello ring mold. I use a vintage 80s Tupperware Jello Ring mold which works great. Tupperware still sells this Jello mold.
• A 6” Tower Mold. This should hold 6 cups. I’m using a vintage Mirro aluminum mold.
• An 11” x 15” Sheet Cake Pan. I use a Wilton 11×15 pan.
• 1/8 Sheet Aluminum Trays. You’ll need two of these for the red and blue Jello squares. I am using the Nordic Ware 1/8 Sheet trays that come in a two pack.
• A stand mixer or hand mixer. I used both!
• A 10” Round Cake Board. Cut down to a 9″ diameter size. You can get a multi pack with both 8″ and 10“ sizes.
• An 8” Round Cake Board. Cut down to a 7″ diameter size.
• A 14” x 19” Cake Board.
• Piping Bags and a Star Tip.

How to make the Fallout Jello Cake:

Step 1: Make the Jello

1. Prep your molds by greasing them with a cooking oil. This will help with releasing the Jello later.
2. For the Jello molds to hold their shape you will need to make them “jiggler” style which means less water. Use 1 cup of water for each 3 oz. box of Jello.
3. Dissolve the Jello in boiling water and pour into the molds. Transfer to the refrigerator and chill until firm, at least 3 hours.
4. For the red Jello squares, you will use 1 packet of Jello and 1 cup of water.
5. Dissolve in boiling water and pour into the tray. You want it to be about half full. Discard any remaining liquid.
6. For the blue Jello squares, I found that there was enough Jello liquid left over after filling the Tupperware mold to fill the tray half full.
7. Chill until set, then use a sharp knife to cut into squares. Store in the fridge until ready to use.

Step 2: Make the Cake

1. Follow the instructions on the box cake mix. Once cooled, cover and set aside while you make the frosting. Make sure the cake is flat and level on top or your Jello will lean like the tower of Pisa.

Step 3: Make the frosting

1. With a hand mixer or stand mixer fitted with the paddle attachment, whip the softened butter on medium speed for about 2 minutes until creamy.
2. Add the powdered sugar, then the heavy cream, and continue mixing on low to incorporate, then switch to medium-high speed and beat for another 2 minutes. Add salt as needed and mix well.
3. If your frosting is too thin for piping, add more sugar. If it seems too thick add more cream.
4. Add about 2 cups of the frosting to a small bowl and mix in yellow food coloring until you achieve a pale yellow color.

Step 4: Frost the Cake

1. Frost the cake with the white frosting. Just the outside, we aren’t doing any layers.
2. Add the yellow frosting to a piping bag and use the star tip to pipe a border along the top and bottom edge of the cake.
3. Store the cake in the fridge uncovered for at least ½ hour to help the frosting set up firm.

Step 5: Make the whipped cream

1. Beat cold whipping cream and sugar on medium-high speed until stiff peaks form.
2. Add to a piping bag with a star tip and store in the refrigerator until needed.

Step 6: Plate the Jello

If you put the Jello directly on top of the frosted cake it will eventually start to “leak water” and melt all over the cake. To avoid this you will need to place the Jello molds on cardboard cake rounds first. This also helps the Jello layers sit flat on top of each other and the cake.

1. To fit the Jello molds you will need to cut the 10” round down to a 9” size and the 8” size down to a 7” size.
2. Now, carefully transfer your Jello molds onto the cake rounds. Try to get them dead center on the boards or the whole thing will tilt (ahem, like mine). I know, easier said than done…

Step 7: Assemble the Jello Cake

1. Place the blue Jello mold in the center of the cake.
2. Place the red Jello mold on top of the blue Jello.
3. If it hasn’t collapsed yet, proceed with piping the whipped cream around the Jello making sure to hide the cardboard cake rounds.
4. Throw a few of the red and blue Jello squares around the edges.
5. Now add your “congrats” cake topper on top and pat yourself on the back for completing this monumental Jello Cake challenge.
6. Serve immediately.

Tips for getting Jello to release from the mold:

• Always grease the mold ahead of time.
• Dip the outside of the mold in hot water for a few seconds to help it release. Anywhere from 5 seconds to 30 seconds depending on how hot your water is. Keep in mind that the aluminum mold will heat up faster than the plastic one, so go in 5-second intervals and keep an eye out for when the outer edge starts to look loose. Then you know it’s ready.
• If it looks too runny you have melted it too much. Just stick it back in the fridge for a few minutes to re-solidify.

Can I use a different Jello mold?

Yes, you can. Just make sure you do the math if you are using anything larger or smaller than the sizes recommended in this recipe. You need a minimum 2” difference in size between your two Jello molds, and your sheet cake needs to be at least 4” wider than the base Jello layer.

How long will the Fallout Jello Cake keep?

It is best if this cake is consumed the day you make it, mainly because the little Jello squares on top of the frosting will start to melt. However if you have leftovers, just remove those decorations then cover the whole cake tightly with plastic wrap and store in the fridge up to 5 days.

How to transport the Fallout Jello Cake:

This one is easy. Just don’t. Any attempts to move this 25lb wobbly beast in a car will end in tears…and Jello Cake all over the dash. Simply moving it from the counter to the table will be an Olympic challenge. If your party is more than 8ft from the kitchen, I suggest assembling the components on site.

The Fallout Jello Cake cheat:

There is one cheat I will mention if you are short on time (or you stink at frosting and piping a cake): Buy a pre-made custom 1/2 sheet cake. Most grocery stores will accommodate this. This will save you loads of time, and it will also look perfect.

I hope I’ve provided some helpful tips for creating your very own vault dweller Jello Cake. Leave a comment and let me know how yours turned out.

Cheers!

-Jessica

More Jello & Treats to explore:

• Dreamy Raspberry Cranberry Jello Salad Mold
• Easy Green St. Patrick’s Day Jello Salad
• The Ultimate Fudgy Cocoa Brownies
• Sinfully Decadent Einkorn Salted Butterscotch Cookies

Now Milton, let's not be greedy. Share it!