This rainbow layer cake is sure to make any birthday magical

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πŸŽ‰ Are you searching for the perfect centerpiece for your next birthday bash? Look no further! This Multi-Layer Rainbow Birthday Cake is not just a cake, it’s a party in itself!

Why this rainbow cake?

🍰 Vibrant Layers – Every slice reveals a burst of color that will wow your guests!

🍦 Delicious Vanilla Frosting – Smooth, creamy, and perfectly sweet!

🌟 Decorated with Rainbow M&Ms – Adds a fun, crunchy twist to every bite!

🎈 Perfect for All Ages – Kids and adults alike will love the festive look and taste!

πŸ“Έ Instagram-Worthy – Make your party unforgettable with this stunning cake as the star!

Multi-Layer Rainbow Birthday Cake with Vanilla Frosting and M&M Decoration


For the Cake:

  • 3 cups all-purpose flour
  • 1 tablespoon baking powder
  • 1/2 teaspoon salt
  • 1 cup unsalted butter, softened
  • 2 cups granulated sugar
  • 4 large eggs
  • 2 teaspoons vanilla extract
  • 1 1/2 cups whole milk
  • Food coloring (red, orange, yellow, green, blue, and purple)

For the Vanilla Frosting:

  • 1 1/2 cups unsalted butter, softened
  • 6 cups powdered sugar
  • 1/3 cup heavy cream
  • 2 teaspoons vanilla extract
  • Pinch of salt

For Decoration:

  • 2 cups rainbow M&Ms


1. Prepare the Cake Batter:

  • Preheat your oven to 350Β°F (175Β°C). Grease and flour six 8-inch round cake pans (or bake in batches if you don’t have six pans).
  • In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.
  • In a large bowl, beat the butter and sugar together until light and fluffy. Add the eggs one at a time, beating well after each addition. Mix in the vanilla extract.
  • Gradually add the dry ingredients to the butter mixture, alternating with the milk, beginning and ending with the dry ingredients. Mix until just combined.

2. Color the Batter:

  • Divide the batter evenly into six bowls.
  • Add a different food coloring to each bowl to create red, orange, yellow, green, blue, and purple batter. Mix until the color is evenly distributed.

3. Bake the Cakes:

  • Pour each colored batter into its prepared cake pan.
  • Bake in the preheated oven for 18-22 minutes, or until a toothpick inserted into the center comes out clean.
  • Allow the cakes to cool in the pans for 10 minutes, then turn them out onto wire racks to cool completely.

4. Prepare the Vanilla Frosting:

  • In a large bowl, beat the softened butter until creamy.
  • Gradually add the powdered sugar, one cup at a time, beating well after each addition.
  • Add the heavy cream, vanilla extract, and a pinch of salt. Beat until the frosting is light and fluffy.

5. Assemble the Cake:

  • Level each cake layer by trimming the tops if necessary.
  • Place the purple cake layer on a serving plate and spread a thin layer of vanilla frosting on top.
  • Repeat with the blue, green, yellow, orange, and red layers, spreading frosting between each layer.

6. Frost the Cake:

  • Apply a crumb coat by spreading a thin layer of frosting over the entire cake to seal in any crumbs. Refrigerate for 15-20 minutes to set.
  • Apply a thicker layer of frosting to cover the cake completely, smoothing it with an offset spatula or cake scraper.

7. Decorate with M&Ms:

  • Press the rainbow M&Ms into the frosting in any design you like. You can cover the entire cake with M&Ms, create patterns, or write a message with them.

8. Serve and Enjoy:

  • Slice and serve your colorful, festive rainbow birthday cake!


  • Ensure each cake layer is completely cool before frosting to prevent the frosting from melting.
  • Use gel food coloring for more vibrant colors.
  • If you don’t have six cake pans, bake the layers in batches, cleaning and re-greasing the pans between uses.

Enjoy your beautifully colorful and delicious rainbow birthday cake!

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