Glass block holiday Jell-o is the kind of festive, colorful recipe that instantly brightens a holiday table. I love holiday-themed Jell-o recipes like our Layered Jell-O, but waiting for each layer to set before adding the next can be time consuming. The beauty of this version is that all of the colors can be made and allowed to firm up at the same time. Once set, they are sliced into little cubes, tossed together, and then covered in a sweet, creamy sweetened condensed milk gelatin to hold everything together. The end result looks gorgeous sliced into tidy squares or rectangles and stacked on a serving plate. As a bonus, they are particularly appealing to kids who might turn up their noses at other holiday offerings! They will probably like helping to make these as well; I always think the colored blocks look like Lego when they’re all tossed together!
Ingredients and Equipment Needed
This is just a preview of ingredients and method, keep scrolling for full printable recipe.
Ingredients
- Assorted Jell-O flavors – You’ll need 4-5 colors in the small, 3-ounce packages. Just pick the colors and flavors you prefer.
- Unflavored gelatin – This is what firms up the sweetened condensed milk layer. It’s usually sold in a box of several packets near the other Jell-O. Knox is a common brand name.
- Sweetened condensed milk – NOT evaporated milk. The longer sweetened condensed milk sits in your pantry, the more yellow it will appear. Use a freshly purchased can for the brightest white color!
- Non-stick cooking spray – This is to help the Jell-o release from the pans. Be sure to use a neutral flavored variety.
Equipment
- Food storage containers – Like Tupperware, Rubbermaid, etc. These do not need to all be exactly the same size, they just need to be small enough that about 1 cup of liquid will fill them about 1/4 – 1/2 inch deep.
How to Make Glass Block Holiday Jell-o
- Spray 4-5 small food storage containers with a light coating of non-stick cooking spray (depending on how many colors you’re using) and set aside.
- Bring some water to a boil. Combine each of the Jell-o packets with 1 cup of boiling water and stir until completely dissolved. Allow to cool for a few minutes. Pour each flavor into one of the prepared containers, transfer to the refrigerator, and allow to set for at least 4 hours, or overnight.
- Once set, make the creamy gelatin mixture by combining boiling water with unflavored gelatin and sweetened condensed milk.
- When that mixture has cooled to room temperature, spray a 9×13 pan lightly with non-stick cooking spray and set aside.
- Pull out your colored Jell-o containers and slice them in a grid right in the pan to create little blocks. Empty them all into your 9×13 pan and gently toss the distribute the colors.
- Spread the blocks into an even layer and pour the cooled creamy gelatin mixture over the top. Cover and place in the fridge to firm up for at least 4 hours, or overnight.
- Cut into squares or rectangles and stack on a plate when ready to serve!
Storing and Other Tips
- Store finished Jell-O, tightly covered, cut or uncut, in the refrigerator and enjoy within 3-5 days for best results.
- Don’t worry if your blocks aren’t all the same size, or if they don’t come out of your containers 100% cleanly. Use a silicone scraper to gently pop them out of the food storage containers if necessary. Once they’re all mixed up, you won’t notice the little pieces!
- You can also cut this Jell-O with cookie cutters for fun shapes!
Frequently Asked Questions
Yes! I do not have a replacement for the sweetened-condensed milk, however. If you want to make the entire recipe sugar-free, you may need to experiment with using evaporated milk and a sugar-replacement of your choice in place of sweetened condensed milk for that layer.
You can, just know the top layer is not as pretty as the bottom, so the presentation is not quite as nice that way!
Yes. I’ve seen sweetened condensed coconut milk at some stores that would probably work here!
Definitely! Make it all the way through to the end. You could even cut the squares ahead of time. For best results, I would cut them but leave them in the pan until ready to transfer to a serving plate.
Glass Block Holiday Jell-O
Equipment
- Food storage containers
Ingredients
- 4-5 3-ounce packages assorted Jell-O in coordinating colors
- 2 packets unflavored gelatin (¼ ounce, or 2¼-2½ teaspoons)
- 1 14-ounce can sweetened condensed milk
- non-stick cooking spray neutral flavored variety
Instructions
- Spray 4 small food storage containers (like Tupperware/Gladware/Rubbermaid) with non-stick cooking spray. Set aside.
- Bring 5+ cups of water to a boil. Combine 1 cup boiling water with 1 package of Jell-O, stirring until dissolved. Place the dissolved Jell-O in one of the prepared containers. Repeat with the remaining packages of Jell-O. Refrigerate for at least 4 hours, preferable overnight.
- When the Jell-O has set, bring another 1 ½ cups of water to a boil. While the water is heating, sprinkle 2 packets of unflavored gelatin over ½ cup of cold water. Allow to stand for about 4 minutes. When the water is boiling, pour 1 ½ cups boiling water over the dissolved gelatin and stir to combine. Add the sweetened condensed milk and mix well. Allow to come to room temperature.
- Lightly spray a 9×13″ pan with non-stick cooking spray. Carefully cut the colored Jell-O into cubes (right in the containers) and gently dump/scrape into the 9×13″ pan. Toss gently to distribute the colors and spread into an even layer.
- Pour the cooled milk mixture over the colored Jell-O and, if necessary, rearrange some of the colored Jell-O to make sure it is evenly distributed and not sticking out of the white mixture too far.
- Place the 9×13″ pan in the refrigerator and chill overnight. Cut into squares, rectangles, or various shapes with cookie cutters and serve.
Notes
- Store finished Jell-O, tightly covered, cut or uncut, in the refrigerator and enjoy within 3-5 days for best results.
- Don’t worry if your blocks aren’t all the same size, or if they don’t come out of your containers 100% cleanly. Use a silicone scraper to gently pop them out of the food storage containers if necessary. Once they’re all mixed up, you won’t notice the little pieces!
Questions & Reviews
This is awesome! I would like to make this for a party but want to make it beforehand. I think someone already asked but I couldn’t find an answer, how long do you all think it should keep in the refrig?
thanks!
a day or two is fine.
Sounds yummy and looks fabulous!!
What size containers do you use for the jello to set? Does it matter?
For example if we only use two colors of jello what size containers do you use, height, depth, & width?
There’s really no set size, you’ll just have to eyeball it! Just imagine the size of little squares you want and go from there.
I made this yesterday. It did come out slightly yellow instead of white though, and i used the same ingredients you showed in your picture. But it tasted great and i will definitely make it again!.
Will it be okay to add the sweet condensed milk without mixing it with the unflavored gelatin mix? Do you think the outcome would still be the same?
I totally made this a million times, it wall called Broken Glass Dessert, and instead of sweetened condensed milk it was plain milk with pineapple jello in it, I’m sure this is thicker and richer. We also put it on a graham wafer crust, so there’s a variation for you.
I made this for an 80s party and called them Rubik’s cube jello. They were a huge hit!
Made it for my daughter’s 6th b’day party this past weekend. The theme was rapunzel so used all four rapunzel colore Jell-O. Was a hit!!Thanks for sharing the recipe!
Dear Sara and Kate,
I found your website looking for this multi-colored Jello creation, I’m a few months behind the times but oh well. I’m going to a luau this weekend and I needed something different.
I’m a guy. I can be lazy, and am always looking for shortcuts for recipes. There is only one shortcut for your multi-color Jello. Ice Cube Trays. I made all the Jello squares using a plastic ice cube trays from the dollar store.
Spray the ice cube trays with cooking spray, add Jello, let it sit in the refrigerator. Pop them out with a small rubber spatula. Presto, instant Jello cubes. I ended up using two trays per color. (I doubled the recipe.)
I also made one other change in the recipe to zip up the flavor, but I’ll save that for another time.
You are the only food website I have booked marked.
You both Rock.
Regards,
Bill, that is GENIUS!
it says 4 flavors of jello. but you used 5. did you use all of the jello from the 5? i may never see the reply, with 135 already comments. but thought i’d ask anyways in case i should find it.