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Chocolate Rainbow Cake

chocolate rainbow cake

It is time for Parshat Noach and we needed a new rainbow cake, one for those of us not into making 7 layers of different colored cakes (too much work for me). Plus I prefer a simple chocolate bundt cake. Then all I had to do was decorate with all my colorful Mike and Ike's and for fun I added some rice krispie treats for extra effect. You can make this any time and you can even make one pretty and give the other half to the kids to make their own.

  • Duration
  • Cook Time
  • Prep Time
  • 12 ServingsServings


  • Vegetable oil spray
  • 2 ounces bittersweet chocolate, chopped
  • 3/4 cup coconut oil
  • 1 cup sugar
  • 1 large egg
  • 2 cups all-purpose or white whole wheat flour
  • 1/2 cup Dutch-process cocoa powder
  • 1 tablespoon baking soda
  • 3/4 teaspoon salt
  • 1 cup strong-brewed coffee
  • 1 cup coconut milk mixed with 1 tablespoon lemon juice


  • 1 cup coconut milk
  • 1/4 cup confectioners' sugar
  • Dash salt
  • 1/2 pound bittersweet chocolate, roughly chopped
  • Mike and Ike's (all the colors as needed to make a rainbow


  1. Preheat the oven to 350°. Spray a 12-cup Bundt pan with vegetable oil spray. In a small saucepan, melt 2 ounces of the chopped chocolate over low heat, stirring constantly. Scrape the chocolate into a medium bowl and let cool slightly. Whisk in the oil and sugar until smooth, then whisk in the egg.
  2. In a small bowl, whisk the flour, cocoa powder, baking soda and salt. Add half of the dry ingredients to the chocolate mixture along with 1/2 cup of the coffee and 1/2 cup of the coconut milk mixture; whisk until smooth. Add the remaining dry ingredients, coffee and buttermilk and whisk until smooth.
  3. Pour the batter into the prepared pan and bake in the lower third of the oven for about 45 minutes, or until a toothpick inserted in the center of the cake comes out with a few moist crumbs attached. Let the cake cool on a rack for 10 minutes, then turn it out and let cool completely.

Ganache Frosting

  1. In a large saucepan, bring 1 cup coconut milk, 1/4 cup confectioners' sugar, and dash salt to a boil. Remove from heat; add 1/2 pound bittersweet chocolate, roughly chopped, and let stand, without stirring, for 1 minute. Whisk just until combined. Refrigerate, stirring occasionally, until spreadable, about 1 hour.

Once cake has cooled and ganache is ready you can decorate your cake.  First cut your cake in half.  You can make two rainbow cakes or leave one just covered with ganache.  For the rainbow cake, spread the ganache all over the cake with a knife or spreader, then carefully place Mike and Ike candies to make a rainbow.  If desired you can put rice krispy treats on the bottom to look like clouds.