So listen, Rainbow Jello Cubes weren’t even supposed to be my thing.
It started with a Pinterest-fueled panic the night before my cousin Becca’s baby shower. I’d totally spaced on signing up for something on the potluck list (I was aiming for chips, people—low effort, high reward). But by the time I clicked the link, all the good stuff was taken. Mac and cheese? Gone. Cupcakes? Snagged. Chips and dip? Claimed. Somebody even had fruit salad. Who volunteers for fruit salad?
What was left? “Colorful dessert.” Whatever that means.
I didn’t wanna be that person who brings a sad tray of store-bought cookies and calls it a day. So I did what any irrationally competitive millennial with a sugar addiction would do: typed “cool colorful desserts” into Google and fell headfirst into the gelatin rabbit hole.
Rainbow. Freakin’. Jello. Cubes.
Why Are Rainbow Jello Cubes Even a Thing?
Okay, real talk: Rainbow Jello Cubes are kind of ridiculous. They’re like a dessert and an art project had a neon baby. It’s basically multiple layers of fruity jello, alternating with this creamy, milky layer that’s somehow both nostalgic and slightly confusing in texture—but in a good way. They wiggle. They shine. They’re cold and sweet and bizarrely satisfying.
Also? They look like you tried. Like you spent hours sweating over a stove when really you were just pouring sugar water into a pan and binge-watching “Brooklyn Nine-Nine” while each layer set in the fridge.
But kids love ’em. Grown-ups pretend to be “meh” about it, but you’ll catch them sneaking thirds when they think no one’s looking.
How It Turned Into My Signature Dish
Becca’s baby shower was chaos, like all family things are. There were exactly 47 people in a living room meant for 12. Someone’s toddler was crying because she dropped her juice box. My aunt was already three sangrias deep and aggressively complimenting people’s eyebrows.
And there, in the middle of the snack table, was my tray of Rainbow Jello Cubes. All six layers, cut into perfect little shiny squares.
I thought it would just sit there, getting kind of weird and melty. But then—people lost their minds.
“Oh my god, did you make these?”
“These are so pretty, like Instagram pretty.”
“HOW? Like seriously, how did you DO this?”
I should probably be embarrassed by how smug I was. I wasn’t. I was beaming like I just got handed an Oscar.
And so began my reign as The Jello Girl™.
What You Actually Need (Surprise: It’s Not Much)
Let me demystify this whole rainbow jello cubes thing. It’s not hard. It’s just a little annoying. Like folding fitted sheets or explaining to your mom that the Wi-Fi password is case sensitive.
You’ll need:
- 4–6 boxes of different colored/flavored Jello (I do red, orange, yellow, green, blue, and sometimes purple if I’m feelin’ fancy)
- 2 packets of unflavored gelatin (this is the glue between layers, my friend)
- 1 can sweetened condensed milk
- Water. That’s it. Regular hot and cold water.
- A 9×13 pan (don’t get weird with the size—just use the normal one)
The Layering Process (AKA: The “Hurry Up and Wait” Saga)
This is where it gets a little extra. Each color gets layered with the creamy white part in between. You’ve gotta let each layer chill and firm up before pouring the next or it’ll be rainbow soup. Been there. Still haunts me.
Here’s what I do:
Step 1: Dissolve a box of colored Jello in 1 cup hot water + ½ cup cold water. Pour into the pan. Chill until firm. (About 30 min to an hour depending on your fridge’s vibe.)
Step 2: Mix 2 packets unflavored gelatin with ½ cup cold water. Let it bloom (gelatin talk for “sit there like a weird blob”) for a few minutes. Then pour in 1½ cups boiling water + 1 can sweetened condensed milk. Boom. That’s your white layer.
Step 3: Pour some of the white layer on top of your first color. Chill again.
Repeat the process until you run out of colors, patience, or fridge space.
Warning: This will take hours. Plan ahead. Like, do it the night before and block out your schedule. Maybe get a glass of wine or six.
Cut It Up Like You Mean It
Once everything’s set (you’ll know because poking it doesn’t leave a dent), grab a sharp knife, dip it in hot water, and slice into cubes. Wipe the blade between cuts if you’re trying to be a perfectionist about it.
Pro tip: Line the pan with plastic wrap or parchment if you want to lift the whole slab out first. If you forget (like I always do), just embrace the scoopy chaos.
You’ll get about 80–100 cubes depending on how tiny you go. People will eat five at a time, so plan accordingly. https://potatonion.com/classic-tres-leches-cake/.
When It All Went Wrong (But Still Right?)
So, funny story—at my niece’s third birthday party, I got cocky and tried to make galaxy-themed jello cubes. Tried mixing black cherry, grape, and blue raspberry with edible glitter. Yeah. Edible. Glitter.
It looked like cosmic sludge. Like someone tried to recreate the solar system in a blender. But guess what? Kids loved it. They called it “unicorn poop” and that tray was wiped clean before the cake even came out.
Moral of the story: Even when it’s ugly, rainbow jello cubes slap.
Where to Serve These Weird Little Beauties
Honestly? Everywhere. They fit in at:
- Potlucks
- Baby showers
- School bake sales
- Barbecues
- Tuesday afternoons when you need a win
Also make killer pride party treats if you stick to six classic rainbow layers. Or go pastel for Easter. Or red, white, and blue for the 4th of July. These cubes are basically the drag queens of the dessert world: versatile, flashy, and totally extra.
A Few Extra Thoughts While We’re Here
- If you’re vegetarian/vegan: Look into agar agar. I haven’t tried it (yet), but the Internet says it’s possible.
- Want a grown-up version? Add vodka to the layers. But maybe don’t bring that version to your kid’s soccer banquet unless you wanna get weird looks.
- Want to get artsy? Use cookie cutters instead of slicing into cubes. Hearts, stars, dinosaurs—go wild.
Final Thought Dump
I feel like rainbow jello cubes are one of those foods that look hard but really just take time and fridge space. Like, they’re a commitment. But the kind of commitment that gives back in compliments and second helpings.
Do they wobble like a baby deer trying to walk? Yes.
Do they sometimes stick to your fingers and leave little jelly prints on your shirt? Also yes.
But they’re so worth it.
🎯 Want more chaotic kitchen adventures? Check out this absurd attempt at galaxy popcorn that turned my microwave purple.
Or if you want to go deeper into nostalgic snacks, my friend Jess has this unhinged DIY Dunkaroo recipe. You’re welcome.
