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Melted Rainbow Cake

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  • Prep 2 hr 0 min
  • Total 5 hr 0 min
  • Servings 20
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Mimicking the effect of melting crayons, a rainbow of coloured ganache is dripping down the sides of a bright white cake. Cut into the cake to find specks of rainbow colours as well. Recipe by Hungry Happenings.
Created May 16, 2018
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  • 2 boxes Betty Crocker™ SuperMoist™ rainbow bit cake mix
  • Eggs, water, and oil called for on cake mix
  • 4 containers Betty Crocker™ Whipped fluffy white frosting
  • 3/4 cups white chocolate, finely chopped
  • 1/3 cup heavy whipping cream
  • 2 tablespoons corn syrup
  • Candy colouring - purple, blue, green, yellow, orange, red, pink


  • 1
    Preheat oven to 325°F.
  • 2
    Line a 16x4x4.5-inch loaf pan with non-stick tin foil or grease it with shortening and dust it with flour.
  • 3
    Make one cake mix according to package instructions.
  • 4
    Pour batter into prepared pan.
  • 5
    Bake for 48-52 minutes until a toothpick inserted in the centre of the cake comes out clean.
  • 6
    Cool cake for 10 minutes. Remove from pan and cool on a wire rack.
  • 7
    Clean and rinse pan with cold water and make the second cake as above.
  • 8
    Once both cakes have cooled, cut off the mounded top, and cut each cake into 2 layers.
  • 9
    Frost in between layers and around the cake.
  • 10
    Prepare the ganache by mixing together the chopped (or white chocolate), heavy whipping cream, and corn syrup.
  • 11
    Heat in the microwave on high for 30 seconds. Stir. Heat for 20 seconds, then let set in microwave for 1 minute. Stir. If not all the chocolate is melted, heat for 10 second increments, stirring after each.
  • 12
    Divide ganache into 7 bowls. Colour each bowl of ganache using candy colouring creating a purple, blue, green, yellow, orange and pink.
  • 13
    Start at one end of cake and pour a spoonful of purple ganache over the top edge allowing it to drip down the sides of the cake.
  • 14
    Next to the purple add a spoonful of blue, then green, yellow, orange, red, then pink, repeating this as you go around the entire cake. If desired, swirl the colours on the top of the cake. If the ganache becomes too thick, heat it in the microwave for about 10 seconds to thin it out.
  • 15
    When ready to serve, cut into 20 slices.

Nutrition Information

No nutrition information available for this recipe
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