Rainbow Jello Recipe & Instructions (2024)

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We celebrated Danika’s Birthday this year with an epic rainbow unicorn party and this stunning rainbow jellowas the star of the show! The kids always get to pick their theme and I think it’s become a favorite thing to do. I then take it and run with it! I’ll be sharing all of my ideas from her Rainbow Unicorn themed party and I had to start with my favorite (and the most awe-inspiring thing at the party),Rainbow Jello! It looks difficult, but while it is time-consuming, it is NOT difficult!

This Jello turned out beautiful and was the talk of the party! If you are looking to bring a dish to your next party that will wow the crowd then this is it! If you are planning a rainbow party then this rainbow jello is the perfect rainbow food to serve to your guests! It may look incredibly difficult to make, but rest assured that this recipe is NOT difficult! It’s quite easy if you follow my simple step-by-step instructions. Keep in mind that this Jello takes an entire day to complete since you’ll be doing the layers one at a time and allowing them to set. Give yourself plenty of time to make it and don’t rush it! I would advise making this the day before your party or gathering. It will hold up just fine in the fridge!

Rainbow Jello Recipe

The trick to making the rainbow jello turn out beautiful is to create thin layers and let them set completely before pouring the next layer. It’s very important to follow the directions exactly and let each mixture cool enough so that it doesn’t end up melting the layer below it when you pour it on. If you rush it and pour the next layer on top of your jello before it is set then you’ll end up with layers that run and are mixed. It will still taste fine, but it won’t achieve the layered look you are aiming for.

Rainbow Jello Supplies

If you are planning on making this rainbow jello then make sure you have these ingredients on hand or order them now so you are ready to make this beautiful rainbow jello!

6 small packages (3 ounces) of different Jell-O (I used rainbow colors however you can use as many or as few colors as you’d like and you can change them up for holidays)
4 packages Knox unflavored gelatin(I recommend buying it in bulk in a can instead of all the little boxes-it’s cheaper that way)
1 (14 ounce) can Sweetened Condensed Milk

You’ll also need a glass 9″ x 13″ pan or casserole to make this rainbow jello in.

Knox Original Gelatin, Unflavored Carnation Organic Sweetened Condensed Milk Jell-O Gelatin 3oz All 22 Flavors In A Gift Box With Bonus Color Changing Spoon Fire King Anchor Hocking 9×13 3qt Glass Baking Dish Cooking Oven Bake 13×9

Rainbow Jello Instructions

First layer: Mix 1 package of any flavor jello with 1 tsp Knox gelatin and 1 cup boiling water. Cool and pour into pan; refrigerate until set. Ensure that your fridge shelf is level so your layer sets evenly and doesn’t turn out thick on one side and thin on the other. It takes about 30 minutes to set up in the fridge before you can move on to the next layer. *Important* While waiting for your Jello to set, make the next layer and leave it to cool on the countertop.

Second layer: Mix 1 envelope Knox gelatin (or 2 tsp Knox if using the bulk can) with 1/2 cup hot water until dissolved. Add 1/2 can condensed milk and an additional 1/2 cup hot water. Once cooled pour 3/4 cup (just enough to cover the Jello and make a thin layer) of the milk mixture over the set jello and refrigerate until firm. It takes 30 minutes for this layer to set up in the fridge. As soon as you put the white layer in the fridge to chill make the next color jello so that it will have 30 minutes to cool on the counter.

Repeat first and second layer directions ending with a color jello layer. Half way through the process you will need to make the other half of your white mixture. The first time I made this I made the white layer all in one batch and ended up with a bowl of jelled white mix before I was done because it takes so long for the layers to set. If you find this happens to you then set your bowl of white mixture in another bowl of hot water (underneath it so it’s not mixing with your white mixture) and it will dissolve and liquify again.

Once you run out of white mixture then Mix 1 envelope Knox gelatin (or 2 tsp Knox if using the bulk can)with 1/2 cup hot water until dissolved. Add the other 1/2 can condensed milk and an additional 1/2 cup hot water. Once cooled pour 3/4 cup (just enough to cover the Jello and make a thin layer) of the milk mixture over the set jello and refrigerate until firm. Continue repeating layers until you are done.

*NOTE: I made my white layers thinner than my colored layers. Some readers have commented that they ran out of white mixture. If you make your layers thicker then you will run out. You may want to have a second can of sweetened condensed milk and an extra box of plain gelatin on hand in case you run out!

Once finished, cover with plastic wrap and refrigerate overnight to setuntil firm. Then slice into rectangles or squares and serve! Not only is it beautiful, but it tastes great too!

I began my layers with purple then blue, green, yellow, orange, and red so they would be in correct rainbow order. Remember Roy G. Biv! Red, Orange, Yellow, Green, Blue, Indigo, Violet. We skipped indigo 🙂 In order for them to be red on top, purple on bottom, we started with purple and worked backwards. Of course you’ll also have a layer of white in between each.

Print the Rainbow Jello Recipe below!

Rainbow Jello Recipe & Instructions

Sarah | Must Have Mom

Beautiful rainbow jello that can be modified for many different occasions! Easy to make and so many different color combinations you can do!

3.67 from 3 votes

Ingredients

6 small packages 3 ounces of different jello colors
5 packages Knox unflavored gelatin or buy a bulk can to save money
2 14 ounce can sweetened condensed milk
Water

Instructions

You will make this in a glass 9x13 pan.
First layer: Mix 1 package of any flavor jello with 1 tsp Knox gelatin and 1 cup boiling water. Cool and pour into pan; refrigerate until set. Make sure your pan is on an even surface so your layer is level. It takes about 30 minutes to set up in the fridge before you can move on to the next layer. Important While waiting for your Jello to set, make the next layer and leave it to cool on the countertop.
Second layer: Mix 1 envelope Knox gelatin (or 2 tsp bulk powder) with 1/2 cup hot water until dissolved. Add 1/2 can condensed milk and an additional 1/2 cup hot water. Once cooled pour 3/4 cup (just enough to cover the Jello and make a thin layer) of the milk mixture over the set jello and refrigerate until firm. It takes 30 minutes for this layer to set up in the fridge. As soon as you put the white layer in the fridge to chill make the next color jello so that it will have 30 minutes to cool on the counter.
Repeat first and second layer directions ending with a color jello layer. Half way through the process you will need to make the other half of your white mixture. The first time I made this I made the white layer all in one batch and ended up with a bowl of jelled white mix before I was done because it takes so long for the layers to set. If this happens to you just immerse the bottom of your white mixture bowl in hot water until it liquifies again.
Once you run out of white mixture then Mix 1 envelope Knox gelatin (or 2 tsp bulk powder) with 1/2 cup hot water until dissolved. Add the other 1/2 can condensed milk and an additional 1/2 cup hot water. Once cooled pour 3/4 cup (just enough to cover the Jello and make a thin layer) of the milk mixture over the set jello and refrigerate until firm. Continue repeating layers until you are done. Recipe note: Some readers ran out of white mixture. If you make your white layers too thick you will run out. They should be a thin layer. You may want to have an extra can of sweetened condensed milk on hand just in case you run out!
Once finished, cover with plastic wrap and refrigerate overnight to set. Then just slice into rectangles and serve!