A few weeks ago I embarked on a mission to find a cake that would wow my soon-to-be four-year old daughter on her birthday. I searched online, rummaged through cookbooks, and asked friends. I fell in love with a six layer rainbow-colored cake topped with buttercreme. I was unsure as to how tricky this cake might be, but I just had to give it a try. Unfortunately, the day before I was set to conquer the six layer cake, I had a huge baking disaster which knocked my confidence a bit. You see, I insist on making two cakes – one for each of my children on their birthday. Fortunately for me, my son has simple tastes. He knows what he likes and likes what he knows. For his cake, I decided on a Candy Bar Bundt cake – a deliciously chocolately bundt cake without any need for icing (he does not like icing at all). So, I made his cake first and messed it up beyond belief….and this was to be the easy cake! I managed to calm myself down and enlisted the help of my daughter, thinking her enthusiasm would fuel me, should I feel any doubt about finishing the cake.
The batter for the rainbow cake is a fairly straightforward vanilla cake. You separate it into six bowls (about 1 cup of batter per bowl) and add the gel coloring. Oh, you can’t imagine how these bright colors really lift your spirits. My daughter was positively giddy with excitement stirring the color into the batter. It’s definitely worth investing in the gel colors, as they are so vibrant and do not water down the batter at all.
As I had to use the same pan for each color, the baking process took a very long time. Line pan, pour batter, smooth, bake, cool, clean pan, repeat x 6.
Making the cake batter and baking are the easy part. It’s the layering that’s tricky. I had read that the cake could be quite dry, so I was careful not to overbake, which meant the layers, which are very thin, crack easily. It’s best to take your time and let each layer cool completely before attempting to move them (I can tell you that from experience!).
To increase the moisture of the cake, I spread a very thin layer of apricot jam on each layer before adding the buttercreme. Then end result was very good. Even I was impressed with how good it turned out. as you can see from the photos…I was over the moon, and so were the kids! It really is worth all the time and effort to make a beautiful, show stopping cake that really wows the kids!
I topped the cake simply with tiny candy coated chocolate pieces (like M&M’s, but more colorful). It couldn’t have turned out better. Whew! What a relief! 🙂
Here’s the recipe:
Makes one 9-inch-round six-layer cake
- Vegetable shortening
- 3 cups all-purpose flour
- 4 teaspoons baking powder
- 1/2 teaspoon salt
- 2 sticks (1 cup) unsalted butter, room temperature
- 2 1/3 cups sugar
- 5 large egg whites, room temperature
- 2 teaspoons pure vanilla extract
- 1 1/2 cups milk, room temperature
- Red, orange, yellow, green, blue, and purple gel food coloring
- Preheat oven to 350 degrees. Brush six 9-inch-round cake pans (or as many 9-inch cake pans as you have, reusing them as necessary) with shortening. Line bottom of each cake pan with parchment paper; brush again and set aside.
- In a large bowl, whisk together flour, baking powder and salt; set aside. In the bowl of an electric mixer fitted with the paddle attachment, cream together butter and sugar. Slowly add egg whites and mix until well combined. Add vanilla and mix until fully incorporated. Add flour mixture and milk in two alternating additions, beginning with the flour and ending with the milk. Mix until well combined.
- Divide batter evenly between six medium bowls. Add enough of each color of food coloring to each bowl, whisking, until desired shade is reached. Transfer each color to an individual cake pan. Transfer to oven and bake until a cake tester inserted into the center of each cake comes out clean, about 15 minutes (working in batches if necessary).
- Remove cakes from oven and transfer to a wire rack; let cool for 10 minutes. Invert cakes onto a wire rack; re-invert and let cool completely.
- Using a serrated knife, trim tops of cakes to make level. Place four strips of parchment paper around perimeter of a serving plate or lazy Susan. Place the purple layer on the cake plate. Spread a scant 1 cup buttercream filling over the first layer with a small offset spatula so it extends just beyond edges. Repeat process with blue, green, yellow, and orange layers.
- Place the remaining red layer on top, bottom-side up. Gently sweep away any loose crumbs with a pastry brush. Using an offset spatula, cover the top and sides with a thin layer of frosting (also use any of the excess frosting visible between the layers). Refrigerate until set, about 30 minutes.
- Using an offset spatula, cover cake again with remaining frosting.