How To Make Fruity Pebbles Cake
Step 1: Make the Cake Layers
Preheat the oven to 325°F. Mist three 6-inch round cake pans with nonstick spray, then line the bottoms with parchment paper circles.
In a large mixing bowl, whisk together the cake flour, all-purpose flour, sugar, baking powder, baking soda, and salt.
Add the softened butter and mix on medium-low speed until the mixture looks like damp sand. This should take about 1 minute.
Mix in the eggs one at a time, scraping down the sides and bottom of the bowl after each addition.
Add the milk, Greek yogurt, and orange blossom water. Mix on medium speed for about 90 seconds to aerate the batter and help build the cake’s structure.
Fold in the Fruity Pebbles cereal.
Divide the batter evenly among the prepared pans and smooth the tops.
Bake for 20 to 25 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.
Let the cakes cool in the pans for about 20 minutes. Then turn them out onto a wire rack and cool completely before filling and frosting.
Step 2: Make the Swiss Meringue Buttercream
Combine the egg whites and sugar in a large glass or metal bowl.
Set the bowl over a pot of barely simmering water. Stir continuously until the sugar dissolves completely. To test, rub a little of the mixture between your fingers. It should feel hot and smooth, not gritty.
Remove the bowl from the heat and whip the mixture on high speed until the meringue is thick, white, glossy, and holds stiff peaks.
The meringue should be completely cool before adding the butter. There should be no warmth when you touch the bowl. If needed, refrigerate the meringue for 15 to 20 minutes.
Add the butter one tablespoon at a time, beating well after each addition.
The mixture may look curdled at some point. Keep beating, and it should come back together into a smooth, silky buttercream.
Stir in the lemon extract and salt.
Step 3: Assemble the Cake
Place one Fruity Pebble cake layer on a serving plate or cake stand. Spread an even layer of buttercream over the top. Add the second cake layer and spread with more buttercream. Place the final cake layer on top and frost the entire cake with a smooth layer of buttercream.
Step 4: Decorate with Rainbow Frosting
Scoop about 1/3 cup of frosting into each of 5 small bowls. Tint each bowl with gel paste food coloring in pink, yellow, green, blue, and purple. Pipe horizontal stripes of colored buttercream around the cake’s sides.
Use an offset spatula or pastry scraper to smooth the frosting and slightly blend the colors.
Fit a pastry bag with a 4B tip and fill it with the remaining untinted buttercream. Pipe star shapes all over the top of the cake. Finish with gold sugar pearls, gold sparkling sugar, and gold disco dust.