Rainbow Rice Krispie Treats are a festive and fun treat for St. Patrick’s Day. Made from rice krispie cereal, melted marshmallows, butter and food coloring. These sweet, crispy treats are a deliciously easy dessert.
No baking required, so these colorful treats come together quickly and it’s a dessert the whole family will love.

Rainbow Rice Krispie Treats
Everyone loves delicious cereal treats and here you can take this traditional recipe and kick it up a notch when you make it into a rainbow dessert.
Why We Love Rainbow Rice Krispie Treats
Why is this the best rice krispie treat recipe? Because it’s fairly quick, super easy to make and always a crowd pleaser!
Rainbow desserts are a fun idea for all kinds of occasions, not just St. Patrick’s Day. These are the perfect rice krispies treats for a unicorn party, rainbow birthday party, even a Hawaiian themed party!
Plus, this favorite no bake dessert isn’t just for kids, adults still love this buttery mix of cereal and gooey marshmallows too.
They are super easy to transport, just like these Rainbow Sugar Cookies, which also makes them a great treat for potluck gatherings. Speaking of cookies, have you ever tried delicious Oatmeal Rice Krispie Cookies?
Need an amazing dinner recipe too? Try this fork tender Dutch Oven Corned Beef and Cabbage dish.
More Rainbow Treats to Love
Rainbow Sugar Cookies: a swirl of colors within a sweet sugar cookie.
For a healthy refreshing treat, try these Rainbow Fruit Popsicles made with fresh fruit and juices.
How do You Color Rice Krispie Treats?
To get rainbow rice krispie treats, we’ll add gel food coloring to the melted butter and marshmallows mixture. Each color is mixed in separate bowls, just like in these Easter Rice Krispie Treats recipe, which also includes a chocolate dip and sprinkles.
You’ll also want to do this before adding in the rice crispy cereal to the mix.
Tip: If you forget to blend the colors into the marshmallow mixture first, it does get a little more difficult to make, but it can be done! Spray your hands with nonstick cooking spray and knead each batch by hand until the colors are completely incorporated.
Kitchen Tools
Large Microwave-safe bowl
6 Medium Bowls
Silicone Spatula
Wax Paper (preferred, but you can also use parchment paper)
Square Baking Pan (8×8 or 9×9)
Serrated Knife
Ingredients
Rainbow rice krispie treats only need a few simple ingredients:
Rice Krispies Cereal: 15 cups rice krispies. Use a fresh box of rice crispy cereal as an already opened box could be starting to stale.
Miniature Marshmallows: 4 cups of mini marshmallows (two 16 oz bag of marshmallows). You can use the regular marshmallows as well, but the mini marshmallows are easier to melt. Also, make sure you are using fresh marshmallows. Don’t use a bag that’s already been opened.
Butter: Use unsalted butter for this cereal treat recipe. Melt butter with the mini marshmallows to create a gooey marshmallow mixture.
Salt: Just a smidge is all you need, but it does add a that something extra.
Gel Food Coloring: We’re using 6 colors in these rainbow rice krispies treats: red, orange, yellow, green, blue and purple. For brighter colors, use gel food coloring.
Non-stick Cooking Spray: A few spritz on the paper to keep these cereal treats from sticking.
Directions
For this simple no bake dessert, here’s how to assemble this rainbow rice krispie treats recipe:
Step 1: Prepare a 8×8 (extra thick treats) or 9×9 inch pan with wax paper. Lightly spray the paper with a little cooking spray.
Step 2: To melt butter and marshmallows, add together in a large microwave-safe bowl. Heat in the microwave for 1 minute and then stir. Repeat the heating cycles, stirring vigorously between each, until the marshmallows are completely melted and smooth.
Step 3: Add salt (1/2 tablespoon) and stir well.
Step 4: Pour melted marshmallow mixture into six separate bowls. Add the different colors of gel food coloring to each bowl of the melted marshmallow mixture and stir until completely combined.
Step 5: Use a spatula to fold 2 ½ cups of cereal into each bowl. Stir until the cereal is fully coated in the marshmallow mixture. Make sure to coat completely, don’t leave any dry cereal pockets.
Step 6: Using a buttered spatula press mixture into prepared pan (lined with wax or parchment paper) in even layers to create the stripes of colors when cut. Make sure your paper overhangs the edges of the baking dish to easily remove later.
The first layer on the bottom is the red rice krispies followed by orange, yellow, green, blue and the top layer is purple. Press the layers firmly together.
Tip: If the cereal layers are taller than the top of your dish, keep molding the cereal into the square shape as you stack the layers.
Step 7: Let these rainbow rice krispie treats cool completely before removing them from the pan or cutting them into squares (approximately 1-2 hours).
Step 8: Lift the cereal from the baking dish using the waxed paper edges and place on a cutting board. Using a serrated knife, remove any crooked edges (feel free to eat those, I won’t tell!). Cut the whole square in half and then slice each half into servings, approximately 1 inch thick.
How to Store Rainbow Rice Krispie Treats
In all honesty, Rice Krispies treats have the best flavor and texture the same day they are prepared. If you’re not going to eat them right away, you can freeze them asap; however, they are still not as wonderful as the first day you make them. Let set at room temperature to defrost before serving.
For leftovers, these can be stored at room temperature in an airtight container for up to 3 days. Place a piece of wax paper between each krispy treat to keep them from sticking to each other.
The key is making sure that they are kept in a dry place so that they don’t absorb any moisture that could them soggy.
It’s fun to celebrate with the colors of the rainbow, especially when it is a no bake easy recipe to make.
Celebrate St. Patrick’s day with these colorful Rainbow Rice Krispie Treats for a fun, delicious dessert your friends and family will love.
Enjoy!
Rainbow Rice Krispie Treats

Rainbow Rice Krispie Treats are a festive and fun treat for St. Patrick's Day. Made from rice krispie cereal, marshmallows, butter and food coloring. These sweet, crispy treats are a deliciously easy dessert.
Ingredients
- 15 cups Rice Krispies Cereal
- 2 (16 ounce) bags Miniature Marshmallows
- 12 tablespoons Butter
- 1/2 tablespoon Salt
- Gel Food Coloring (red, orange, yellow, green, blue, purple)
- Non-stick Cooking Spray
Instructions
- Prepare a 8x8 or 9x9 inch pan with wax paper. Spritz the paper with a little cooking spray.
- Melt butter and marshmallows in a large microwave-safe bowl. Heat in the microwave for 1 minute and then stir. Repeat the heating session, stirring vigorously between each, until the marshmallows are completely melted and smooth.
- Mix in salt.
- Pour mixture into six separate bowls.
- Use a spatula to fold 2 ½ cups of cereal into each bowl. Stir until the cereal is completely coated.
- Using a buttered spatula press each rice krispie mixture into baking pan in even layers. First layer is red followed by orange, yellow, green, blue and purple. Press the layers firmly together.
- Let cool completely (1-2 hours).
- Lift the cereal from the baking dish using the waxed paper and place on a cutting board. Using a serrated knife, remove any crooked edges. Cut the square in half and then slice each half into servings, approximately 1 inch thick.
Notes
See recipe post for tips.
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Nutrition Information:
Yield:
12Serving Size:
1Amount Per Serving: Calories: 236Total Fat: 12gSaturated Fat: 7gTrans Fat: 0gUnsaturated Fat: 4gCholesterol: 31mgSodium: 274mgCarbohydrates: 30gFiber: 0gSugar: 4gProtein: 2g
Nutritional values are estimates and not exact.