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Rainbow Bundt Cake

Print Recipe
A bright and festive rainbow hidden right inside a vanilla bundt cake!

Equipment

  • 1 Circle Bundt Pan
  • piping bags
  • bowls & spoons

Ingredients

White / Rainbow Bundt Cake

  • 3/4 cup buttermilk room temperature
  • 2/3 cup sour cream room temperature
  • 4 egg whites room temperature
  • 1/3 cup vegetable oil
  • 1 Tablespoon vanilla
  • 1 15.25oz Box Cake White Mix I used Duncan Hines for the best taste and texture, but any other brand will be similar.
  • rainbow gel colors (red, orange, yellow, green, blue, purple)

White Chocolate Ganache Drip

  • 1 cup "bright white" chocolate candy melts I used Wilton brand, but I also love Sweet Tooth Fairy chocolate melts
  • 1/4 cup heavy cream

Extras

  • 1/2 cup rainbow jimmies/sprinkles

Instructions

For the rainbow bundt cake:

  • Preheat the oven to 325 degrees, and prep your round bundt pan with a swipe of shortening and dust of flour. Set aside.
  • In a large bowl, whisk together all the ingredients for the cake except for the cake mix and food gel colors. Sift in the cake mix and gently stir until it's barely combined.
  • In the 6 separate small bowls, scoop in a generous 1/2 cup of white batter in each bowl. Add one drop(ish) of gel coloring in each bowl, and gently stir to disperse the color throughout. Fill 6 piping bags carefully with the colored cake batter (I love to use a drinking glass to fold the piping bags over for filling the piping bags).
  • In the bottom of the circle bundt cake, spread in a small layer of the white cake batter (see video for a better visual). Snip off the tip to create a small circle opening (about the size a small marble could get through.
  • Next, pipe the first color in a ring, avoiding the outside of the first white layer. (I did purple, which technically makes the rainbow upside down - oops! But you can pipe red first for a more traditional look). Tap the pan to make the batter flat before adding the next color.
  • Next, pipe the second color in a ring around the center of that color stripe (see video). Repeat with the remaining colors - remember to tap the pan to keep it flat before adding in the next color.
  • Next, add about 1/2 cup of white cake batter into another piping bag. Pipe a white layer in the middle again (just like the previous layers), and tap the pan to flatten.
  • Finally, pipe the rest of the white cake batter around the top in an even layer. Bake for 25-27 minutes until the center of the cake is baked through. Remove the bundt cake from the oven, let cool in the pan for about 30 seconds, then flip the bundt cake onto a wire rack to cool completely.

For the White Chocolate Ganache Drip

  • In a glass microwave-safe bowl, stir together the white chocolate candy melts and heavy cream. Heat for 1 minute, then stir until smooth. You may need to add another 15 seconds and stir again if needed. Add to a drip bottle, let cool slightly, then add the drip to the cake. Immediately add on the sprinkles.
  • Slice to reveal your hidden rainbow, and enjoy!

Video