This rainbow fruity pebble cake is so much fun! Moist & perfectly sweet, with tons of crunchy fruity pebbles sprinkled all throughout! Don’t forget the colorful frosting and sparkly gold glitter garnish!

Triple layer rainbow fruity pebble cake with gold sprinkles, with a slice cut out and fruity pebbles scattered on a light gray background.

Hey there! We are just a few days out from St. Patrick’s Day and I’m so happy to be sharing this dazzling Rainbow Fruity Pebble Cake with you!

Rainbow fruity pebble cake on a stand with text overlay.

You can’t have St. Patrick’s Day without rainbow treats, right??

And what a treat this is! It’s a towering triple layer beauty, with crunchy bits of fruity puffed rice cereal running all throughout.

The bright, citrus-y fruit flavor of fruity pebbles really shines in this cake! It’s a lot like funfetti, but WAY better because of all that added flavor!

Rainbow fruity pebble cake with gold sprinkles, on a cake stand with fruity pebbles cereal scattered on a pale gray background.

The cake layers are filled and frosted with a lemon-y Swiss meringue buttercream that’s as luscious as it is beautiful. You’re going to need a little more frosting than usual for this beauty (this is 1 1/2x my normal batch), just because we’re tinting it in several different colors, piping horizontal stripes around the sides, and then blending them together with a spatula or pastry scraper. It gives the most beautiful sunset/rainbow effect!

If you’ve never made this kind of frosting before, definitely check out this Swiss meringue buttercream post. It’s got TONS of great info, and tips on how to avoid all the most common pitfalls.

Once your rainbow fruity pebble cake is filled and frosted, it will need a little extra sparkle! There’s always a pot of gold at the end of every rainbow, right? So top it off with some sparkly sugar pearls, edible glitter, and gold disco dust!

What a stunner! This cake will make your St. Patty’s totally unforgettable!

Rainbow fruity pebble cake with gold sprinkles on a cake stand with green plates, fruity pebbles cereal, and gold forks on a light gray background.

More great cake recipes on my “Cake Recipes” Pinterest board!


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Rainbow Fruity Pebble Cake
Prep Time
1 hr 40 mins
Cook Time
20 mins
Total Time
2 hrs
 
This rainbow fruity pebble cake is so much fun! Moist & perfectly sweet, with tons of crunchy fruity pebbles sprinkled all throughout! Don't forget the colorful frosting and sparkly gold glitter garnish!
Course: Dessert
Cuisine: American
Keyword: rainbow fruity pebble cake
Servings: 10 to 12
Calories: 1095 kcal
Ingredients
For the Fruity Pebble cake layers:
  • 1 1/2 cups cake flour
  • 3/4 cup all-purpose flour
  • 1 cup granulated sugar
  • 1 1/2 teaspoons baking powder
  • 3/4 teaspoon baking soda
  • 3/4 teaspoon kosher salt
  • 3/4 cup unsalted butter, softened
  • 3 large eggs
  • 2/3 cup milk
  • 1/2 cup Greek yogurt (sour cream or buttermilk may be substituted)
  • 1 1/2 teaspoons orange blossom water (vanilla may be substituted)
  • 1 1/2 cups Fruity Pebbles cereal
For the rainbow Swiss meringue buttercream:
  • 9 large egg whites
  • 3 cups granulated sugar
  • 3 cups unsalted butter, softened but still cool
  • 1 1/2 teaspoons lemon extract
  • 1/4 teaspoon kosher salt
Instructions
To make the Fruity Pebble cake layers:
  1. Preheat the oven to 325 degrees F, mist three 6-inch diameter cake pans with non-stick spray, and line with circles cut from parchment paper.
  2. Place the cake flour, all-purpose flour, sugar, baking powder, baking soda, and salt in a large mixing bowl and whisk to combine.
  3. Add the softened butter and mix on medium-low speed until the mixture resembles damp sand (about 1 minute).
  4. Stir in the eggs, one at a time, and scrape the bottom and sides of the bowl with a silicone spatula.
  5. Add the milk, Greek yogurt, and orange blossom water, mixing on medium speed for about 90 seconds to aerate the batter and build the cake's structure.
  6. Fold in the Fruity Pebbles cereal, and transfer the batter equally between the three prepared pans.
  7. Bake for 20 to 25 minutes, or until a toothpick inserted in the thickest part of the cake comes out clean or with a few moist crumbs.
  8. Cool for 20 minutes, then remove the cakes from the pans and cool completely before filling and frosting with rainbow Swiss meringue buttercream.
To make the rainbow Swiss meringue buttercream and decorate the cake:
  1. In a large glass or metal bowl, combine the egg whites and sugar.
  2. Set the bowl over a pot of barely simmering water, and stir continuously, until the sugar is completely dissolved. (Check by rubbing a small amount between your thumb and forefinger; it should be hot to the touch, and feel smooth, not gritty.)
  3. Remove the bowl from the simmering water and whip on high speed until the meringue is thick, white, glossy, and can hold stiff peaks. (It should be cooled completely. There should be no hint of warmth when you place your hand on the side of the bowl. Refrigerate the meringue for 15 to 20 minutes if necessary.)
  4. Add the butter in, a tablespoon at a time, beating well after each addition. (If the mixture begins to look curdled, continue to beat until it comes back together, before adding the remaining butter.)
  5. Stir in the lemon extract and salt.
  6. Place one Fruity Pebble cake layer on a serving plate, and top with buttercream.
  7. Place the next layer on top, spreading on an even layer of buttercream.
  8. Place the last cake layer on top and frost the entire cake with buttercream.
  9. Scoop about 1/3 cup of frosting into 5 small bowls, and tint each one with gel paste food coloring in pink, yellow, green, blue, and purple.
  10. Pipe horizontal stripes in each color around the cake.
  11. Use an offset spatula or pastry scraper to smooth the icing and blend the colors.
  12. Fit a pastry bag with a 4B tip and pipe remaining (untinted) buttercream in star shapes all over the top of the cake.
Nutrition Facts
Rainbow Fruity Pebble Cake
Amount Per Serving
Calories 1095 Calories from Fat 639
% Daily Value*
Total Fat 71g 109%
Saturated Fat 44g 220%
Cholesterol 234mg 78%
Sodium 437mg 18%
Potassium 211mg 6%
Total Carbohydrates 107g 36%
Sugars 83g
Protein 10g 20%
Vitamin A 47.5%
Vitamin C 1.5%
Calcium 9%
Iron 7.2%
* Percent Daily Values are based on a 2000 calorie diet.

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