These are always a huge hit. Ridiculously easy to make, Stained Glass Jello Squares do span two hours to come together, but most of that time is spent with each layer setting up in the fridge while you’re doing something else. You just have to show up every 15 minutes.
They’re also theme friendly. Red, white and green for Christmas, yellow, green and orange for Fall or just green and white for St. Pat’s Day. Now that the jello people have come out with blue, that adds red, white and blue for 4th of July barbecues because yup, these can sit for hours unrefrigerated, even outside in July.
What you’re probably wondering at this point is how they taste. They are delicious. Children particularly love them, but so do adults. The jello contributes the flavor and the cream mixture contributes the sweetness, but the white layers are thin enough so it’s not at all oversweet.
So if you’d like to add these to your repertoire of entertaining fare or something fun to bring to gatherings, here are step by step instructions. (This looks way more complicated than it is because I’m including all the tips, so don’t let the number of words scare you.)
Items needed (assembled in advance):
Metal bowl (or a medium-small saucepan will do).
Glass or plastic 4-cup measuring cup that’s microwave-safe for cream mixture
1-cup liquid measuring cup for boiling water
1/2-cup measuring cup to ladle cream mixture layers
Stirring spoon with a spoon holder of some sort (a little plate works fine)
Pan of water on the stove that you’ll keep bringing back to a boil every 30 minutes.
Cleared out section of refrig shelf space, preferably the bottom shelf.
9″ x 13″ glass baking dish with the whole interior greased with Crisco.
5 boxes of regular jello (not sugarfree) in five colors of your choice
2 boxes (4 envelope packets each) Knox Unflavored Gelatin
1 can Eagle Brand Sweetened Condensed Milk
Heat 4C water on stovetop to a boil.
Meanwhile, assemble your items, grease your baking dish and clear out the fridge shelf. Do stack your jello boxes in the order you’re going to use them, with 1 packet of Knox placed in front of each color (ask me how I know it’s a good idea to do this. The Knox is critical).
Make your first jello color, as follows. All others will be the same:
Open your envelope of jello and the Knox first. Add 1C briskly boiling water into your metal mixing bowl and immediately add the jello and Knox powders, whisking constantly, but gently, until all granules are dissolved. (Aggressive whisking raises bubbles, you don’t want that). Set timer for 30 minutes and let jello mixture cool on counter at room temperature.
Immediately make your whole recipe’s white cream layer mixture: In the 4-Cup, nuker-safe measuring cup, add 1 Cup boiling water and then 2 envelopes of Knox Unflavored Gelatin. Stir to dissolve granules completely, then add the Sweetened Condensed milk, stirring constantly. (Scrape out the huge amount that clings to the inside of the can – you need it all.) Set aside on counter to cool.
Pour your cooled (first) jello layer into the greased 9″ x 13″ baking dish. Place in fridge and set timer for 15 minutes. Immediately make your next jello layer now, as above, so it will have approx. 25-30 minutes to cool.
After 15 minutes from adding your first jello layer, pour 1/2 cup of the white layer into your ladle and quickly drizzle it all over the jello layer, immediately rocking the pan back and forth so every bit of the jello layer is covered. (Important! The white layers set up ridiculously fast upon contact with the cold jello layer, so you need to do the rocking immediately if not quicker.) Return the pan to the fridge in the same direction it was before. Set timer for 15 minutes. (See note below about keeping the white layer’s viscosity.)
After 15 minutes, add your cooled next jello layer, set timer for 15 minutes and immediately make your third jello layer so that it can cool for the right amount of time (25-30 minutes).
Continue as above until you have alternately added all five jello layers with four white layers in between, adding one layer every 15 minutes and always making your next jello layer right after adding the current one.
Important note about keeping white mixture’s correct viscosity: Your white cream mixture will begin to congeal from sitting on the counter as you go along. (See first photo.) Do not try to add it in that state! Before adding your white layers, ALWAYS stir the mixture and if it has thickened, nuke it for 10 seconds on high. Stir and check again, nuking another 5-10 seconds at a time, if needed, until it’s perfectly viscous (but never hot) before adding each 1/2 cup layer. It responds very well to these short nukes because it’s super sweet, and sweet things nuke fast. The second photo shows the thinned out consistency from microwaving and stirring down the thickness, however that’s about the maximum thickness you want to see and thinner yet is better. Just so long as it’s not hot.
Once the final jello layer is on, you can carefully stretch plastic wrap across the top, edge-to-edge of the baking dish, being careful not to let the plastic touch the jello layer since you want it to retain its glass-like surface, and you can store it in the fridge. However, making these the same day as they’ll be served is preferable to the day before.
Slicing the recipe into squares: Use a non-serrated sharp knife so the sides of your squares look glass-like. Also, the sides of your 9″ x 13″ pan are curved, so have your first and last edge cuts be inset about 1/2″ – 3/4″ from all the sides so that all your squares are all straight-sided. To get the straightest, most even slices, insert your knife at the far end of the pan and drag it straight toward you. Lastly, you’ll get less warping of the jello mass (hence more perfect squares) if you make all lengthwise slices first, then do the widthwise ones. From there, you just remove some edge pieces so you can fit your fingers in and remove the squares, several at a time.
♦ ♦ ♦ THE ALL IMPORTANT TIPS ♦ ♦ ♦
♦ Getting level, consistently even layers: Before starting, fill your glass 9″ x 13″ rectangular baking dish half full with water, place onto your fridge shelf and level it, if necessary, with matchbooks or sugar packets so water is same depth on all sides. Then throughout the layering, be sure to put your pan into the fridge in the same direction each time. It’s good to know why: If your fridge shelf is a tad off level, putting the pan in the same direction will, at least, make some of your jello layers consistently thicker, others consistently thinner. That’s fine. What isn’t so fine is when some layers are thick and others are thin, within the same square.
♦ Color choices for first and last jello layers: This is all personal preference but my own is to choose dynamic colors for the top and bottom layers (e.g., red or green). Weaker color layers (yellow, orange or peach) on the ends can wash out so you might find them best used inside. This photo shows a recipe I made using yellow as an outside color and you can see what you think. Purple (grape) is dynamic, but also very dark, as is Black Cherry flavor, so I tend to put the darker colors in the center because they’re harder to see through and they don’t cast their own color reflections on the plate. There are no rules, however, whatever pleases your eye and theme.
Plating and transport: Ideal are the readily-available stiff and sturdy oval platter type disposable plates made by Chinet because not only does their very white color display the jello squares nicely and you can fit a fair number of them on one platter, but they are also somewhat deep-dish so that inverting one plate over another creates a lid which lets you stack them for transport. If you don’t have a box that closely fits the stack, you can wind plastic wrap around the whole stack to keep the platter tops in place.
So that’s how we make these. Inexpensive, fun, tasty and they lend themselves to everything from a wedding to a child’s birthday party and any kind of cuisine party, including those held outdoors. One recipe gives you a ton of squares (figure 3-4 platters worth) and they do fine at room temperature for a long period of time because the Knox prevents the jello from melting and there’s nothing in them that sours or goes bad in the period of time you’d have them out.