Fruity Pebbles Crispy Treat Cake

True cereal treat-lovers will flip for this Fruity Pebbles Crispy Treat Cake! Three layers of chewy, cereal goodness are covered with the lightest coat of buttercream.

Fruity Pebbles Crispy Treat Cake

Ah, Fruity Pebbles. My childhood in a bowl.

I’m still fond of this cereal. My favorite part is the purplish-grey milk that’s left behind after all of the pebbles have been eaten. It’s a last sip of super-sweet concentrated cereal flavor, which is delicious despite how weird it looks.

This was my first time making Fruity Pebbles Treats, which I should have been making all along. They are just as crave-worthy as their Krispie Treat cousins, but more colorful and bright-tasting. They look like a celebration, so of course I had to make a Fruity Pebbles Treat party cake!

Prehistoric cake topper!

Do you like the glittery fella on top? I think he’s pretty cute. I figured since Fred Flintstone is the spokesperson for Fruity Pebbles, a dinosaur might make a fitting cake topper. The plastic Stegosaurus is from Target and fancied it up with paint and glitter. I also had a little Saber-toothed tiger from a previous project, so he’s all sparkly now, too! These are so easy to DIY, I decided to take some pictures of the process so you can try it, too.

Steps for success.

  • First, you’ll need some gold acrylic paint. Use acrylic because it is non-toxic, and make sure the bottle is clearly labeled “Non-Toxic”. I found the paint at Target in the crafting aisle (20 Karat), and the glitter I used is Disco Dust (Soft Gold). This glitter is often used on edibles because it is non-toxic. You’re not supposed to eat it but many people do. It’s biologically inert, which essentially means it has no ability to harm you but it won’t give you any nutrition either. We’re not eating the dinosaur topper, of course, but it’s best to use food-safe elements just in case a flake of glitter floats onto the cake’s surface.
  • Place the dinosaur on a paper plate. Brush the gold paint all its body. You can hold the unpainted dinosaur head between two fingers and turn it as you paint the entire body. 
  • Cover the body with glitter and let dry. After the body is dry, you can paint and glitter the head. this is a good time to paint any spots you may have missed earlier, too.
  • Let the dinosaur dry completely. When dry, pick up the dino and tap its feet on the paper plate so that any loose glitter will fall away. Discard the glitter and paper plate, and then marvel at your glittery new friend!

Get the big box!

You’ll need a family-sized box (15 oz.) of Fruity Pebbles cereal for this cake, and a whole bunch of mini marshmallows! The ratio of marshmallow in this recipe is greater than that of regular crisp rice treats. It makes the finished cake soft, which means it’s easy to cut. The texture is just as crispy and chewy as you’d imagine.

I used my favorite 7-inch pans to form the layers of this cake, and you can find them here. Three 8-inch pans will also work, but keep in mind the overall cake will be a little shorter.

Fruity Pebbles Crispy Treat Cake
Fruity Pebbles Crispy Treat Cake

A smidgen of buttercream.

I used just enough vanilla buttercream to stick the three treat layers together and to fill in the cracks and crevices on the exterior of the cake. The marshmallow treat portion of the cake is already very sweet, so I didn’t want to overwhelm the finished cake with loads of buttercream.

Fruity Pebbles Crispy Treat Cake

As far as cakes go, Fruity Pebbles Crispy Treat Cake is pretty quick to make. There’s no baking, just cooking the marshmallow mixture on the stove top. It’s so full of fun color and you can get really playful with your choice of dino topper (and maybe birthday candles)!

Fruity Pebbles Crispy Treat Cake

Heather Baird
This cereal treat cake is easy to make and fun to serve. There's no baking, just cooking the marshmallow mixture on the stove top. 
5 from 1 vote
Prep Time 20 minutes
Cook Time 15 minutes
Total Time 35 minutes
Course Dessert
Cuisine American
Servings 12


Fruity Pebbles Treat Layers

  • 15 ounce 425g box Fruity Pebbles cereal
  • 10 tablespoons 142g unsalted butter
  • 12 cups 700g mini marshmallows
  • 2 teaspoons vanilla extract
  • Pinch of salt


  • 1 cup 226g of unsalted butter, softened
  • 3 cups 340 g confectioners’ sugar
  • Milk or heavy cream optional
  • 2 teaspoons vanilla extract


Fruity Pebbles Treat Layers

  • Grease three 7-inch spring-form pans or (or three 8-inch pans) with butter; set aside.
  • Remove 1/4 cup of cereal and set aside for later use.
  • Melt the butter in an extra-large pot over medium heat Add marshmallows; stir until melted. Add vanilla extract and stir to combine. Add remaining box of cereal contents to the marshmallow mixture. Stir together with a large spoon until all the cereal is coated with marshmallow. Quickly divide and press the cereal into the pans with well-buttered hands. I often cover a length of wax paper or parchment paper with cooking spray and press it on top of the cereal mixture to pack it down into the pans (be careful –it’s hot!). Refrigerate cake layers in the pans until well chilled and set, about 2 hours.

For the frosting

  • Mix together the butter and confectioners’ sugar in a stand mixer fitted with the whisk attachment. Begin mixing on low speed until crumbly, and then increase to high and beat for 3 minutes, adding milk or cream as needed to thin the mixture. Add vanilla and beat again for another minute until light and fluffy.
  • Transfer 1/3 cup frosting to a piping bag fitted with a large star tip; set aside.
  • Unmold Fruity Pebbles treat layers from the spring-form pans and frost the tops of two cake layers. Stack layers with the unfrosted layer on top; gently press layers together. Place on a cake stand. Frost the outside of the cake with a thin layer of buttercream. I used just enough to fill in the cracks and crevices and then scraped the excess off with a large offset spatula so the cereal is visible on the cake’s edges. You may use more if desired.
  • Pipe stars along the top edge of the cake with the reserved frosting in the piping bag. Scatter reserved 1/4 cup of cereal on top of the stars. If birthday candles are being used, pipe more frosting onto the center of the cake and stand candles upright in the frosting. Let cake come to room temperature before cutting. Use a large chef’s knife to cut the cake into slices.
Keyword american buttercream, fruity pebbles cereal, mini marshmallows
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7 years ago

You are definitely true to form here! Such a fancy looking cake made out of crispy pebbles! Looks so fantastic!

7 years ago

I adore this! Fruity Pebbles were also my favorite breakfast cereal as a kid. I still dream about eating it sometimes 🙂

Coco Cake Land
Coco Cake Land
7 years ago

Oh my gosh. Can I just pour milk over this whole cake and GO NUTS? Love the glittery food-safe dino!!! XO

7 years ago

Breakfast of champions!!!!!

2 years ago

OMG This cake! I must make it!
Like you, I just love cereal, especially the sugary ones. Keeps the kid inside young!