Rainbow Surprise Loaf Cake

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This Rainbow Surprise Loaf Cake is SO easy to make and the kids will absolutely love it! Such a cute idea for a birthday party and you can use any shape for the surprise inside.

Easy Rainbow Birthday Surprise Loaf Cake

You can also use this fun cake idea for Holiday themes like this Heart Loaf Cake we made for Valentine’s Day, etc…

Rainbow Surprise loaf Cake Ingredients

  • 2 boxes of vanilla cake mix
  • 6 eggs
  • 1 cup canola oil
  • 1 cup water
  • Purple, pink, blue and teal gel coloring
  • 4 disposable piping bags
  • cookie sheet with parchment paper
  • loaf pan
  • star cookie cutter


How To Make Rainbow Surprise Loaf Cake

  • Make the 2 white cake mixes according to the boxes
  • Mix one box into a medium bowl and the other into another medium bowl.
  • Take the second white bowl and split it into 4 bowls.
  • Take the color and add a color to one bowl each.
  • Scoop 1 color of the 4 batters into one piping bag.
  • Repeat with remaining 3 colors
Easy Rainbow Birthday Surprise Loaf Cake
  • Using the cookie sheet with parchment paper, take 1 of the piping bags, cut the tip off, pipe one line of the color batter from side to side.
  • Repeat with the other colors. Example: purple, pink, teal, green, purple, pink, teal, green until the pan is covered in colorful lines.
Easy Rainbow Birthday Surprise Loaf Cake
  • Bake the cake at 350 degrees for for 20 minutes or until cake is baked and a toothpick comes out clean.
  • Take the star cookie cutter and cut out star shapes.
Easy Rainbow Birthday Surprise Loaf Cake
  • Take your loaf pan and spray pam all over it.
  • Pour some of the plain cake batter into the bottom of the pan.
Easy Rainbow Birthday Surprise Loaf Cake
  • Take your star shapes and place them standing up into the batter that is already in the loaf pan.
  • Slowly pour the remaining batter around the stars so that when it bakes, the batter will bake over the stars and you won’t see them.
  • Bake at 350 for 30-40 minutes or until a toothpick comes out clean
  • Set aside and let cool before taking out and placing on your favorite serving dish.
Easy Rainbow Birthday Surprise Loaf Cake

Vanilla royal icing

  • 3 whites
  • 1/4 tsp cream of tarter
  • 3 C powder sugar plus 1/2 c on stand by
  • 1 tsp vanilla
  • Pink and Green gel food coloring
  • Confetti Sprinkles


Combine all ingredients, except the colors and sprinkles, into a standing mixer and beat until stiff peaks form.
Add the extra half cup of powder sugar if the royal icing looks like soup once stiff peaks forms. Split into 3 add the two colors into the bowls, mix until you have your desired color, leaving one bowl white.  Add the white icing first over the loaf and then drizzle the pink and green
add the sprinkles.

Easy Rainbow Birthday Surprise Loaf Cake

Now you have this adorable Surprise Loaf Cake that the kids will absolutely LOVE!

Easy Rainbow Birthday Surprise Loaf Cake

Here is a close up of the surprise…

Easy Rainbow Birthday Surprise Loaf Cake

This is a fun cake to let the kids help make as well. Would be so cute for a Unicorn themed party!

Easy Rainbow Birthday Surprise Loaf Cake

Other Fun Rainbow and Unicorn Recipes

5 from 1 vote

Rainbow Surprise Loaf Cake

This Rainbow Surprise Loaf Cake is such a fun and easy recipe to make for a birthday party!
Servings: 12 servings
Prep: 20 minutes
Cook: 50 minutes

Ingredients
  

Surprise loaf Cake:

  • 2 boxes vanilla cake mix
  • 6 eggs
  • 1 C canola oil
  • 1 C water
  • Purple, pink, blue and teal gel coloring

Vanilla royal icing:

  • 3 whites
  • 1/4 tsp cream of tarter
  • 3 C powder sugar plus 1/2 c on stand by
  • 1 tsp vanilla
  • Pink and Green gel food coloring
  • Confetti Sprinkles

Instructions

  • Make the 2 white cake mixes according to the boxes
  • Mix one box into a medium bowl and the other into another medium bowl.
  • Take the second white bowl and split it into 4 bowls.
  • Take the color and add a color to one bowl each.
  • Scoop 1 color of the 4 batters into one piping bag.
  • Repeat with remaining 3 colors
  • Using the cookie sheet with parchment paper, take 1 of the piping bags, cut the tip off, pipe one line of the color batter from side to side. Repeat with the other colors. Example: purple, pink, teal, green, purple, pink, teal, green until the pan is covered in colorful lines.
  • Bake the cake at 350 degrees for for 20 minutes or until cake is baked and a toothpic comes out clean.
  • Take the star cookie cutter and cut out star shapes.
  • Take your loaf pan and spray pam all over it.
  • Pour some of the plain cake batter into the bottom of the pan
  • Take your star shapes and place them standing up into the batter that is already in the loaf pan.
  • Slowly pour the remaining batter around the stars so that when it bakes, the batter will bake over the stars and you won't see them.
  • bake at 350 for 30-40 minutes or until a toothpick comes out clean
  • set aside and let cool before taking out and placing on your favorite serving dish.

Icing:

  • Combine all ingredients, except the colors and sprinkles, into a standing mixer and beat until stiff peaks form.
  • Add the extra half cup of powder sugar if the royal icing looks like soup
  • once stiff peaks form split into 3
  • add the two colors into the bowls, mix until you have your desired color, leaving one bowl white
  • Add the white icing first over the loaf and then drizzle the pink and green
  • add the sprinkles
  • enjoy

Last Step:

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Nutrition

Calories: 639kcal | Carbohydrates: 100g | Protein: 7g | Fat: 24g | Saturated Fat: 4g | Cholesterol: 82mg | Sodium: 643mg | Potassium: 106mg | Fiber: 1g | Sugar: 66g | Vitamin A: 120IU | Calcium: 201mg | Iron: 2.1mg

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