Guest Post: Rainbow Cake via Erica Prather

Note: This is a guest post from my once-roommate, once-colleague, always-a-friend, Erica Prather. I’m the cook, she’s the baker. It’s not unusual to see her clothing and face, marked in flour, with splattered chocolate on her cabinet walls – the sign of an involved, passionate baker. She put together a beautiful and FUN, rainbow cake. Enjoy.

Some weeks ago, I was working away and needed a distraction. “Grace,” I whined, “Send me something pretty.” She linked me to Black*Eiffel, with a feature on a little girl’s birthday party, complete with photographs of a 6 layer, rainbow colored cake. I squealed with delight. That is the most amazing thing I’ve ever laid my eyes on. I thought. I must make that, now.

I didn’t want to wait for someone’s birthday or a certain event, I wanted to create this colorful monstrosity immediately. That weekend, I went skiing in the Sangre De Cristo mountains of Southern Colorado (Wolf Creek to be exact), and in the warmth of a little cabin I created the 6 layer, Roy G. Biv cake.

Roy G. Biv Colorful Cake of Joy:

You can make this cake too, it’s quite easy! The hardest part is getting the layers to stack together. If you’d like to keep things simple (ahem, cheat a bit) you can always just get boxed white cake mix and dye the batter each respective color. I personally made my batter from scratch, tripling a butter cream cake recipe and then dividing it equally into six parts.

I only had two round cake pans to work with, so I had to wait three separate times for all 6 layers of color to bake and cool. You can use a round pan or whatever shape you prefer – just be sure to coat the pan with plenty of oil and flour to prevent sticking! Layer and frost with whatever flavor you prefer. I chose to make a homemade cream cheese frosting.

You can buy food coloring at any grocery store; the instructions on the back will let you know how many droplets of each color are needed to combine and make non-primary colors, or you can just play around with it until you get the color you’d like!

Baking At High Altitude:

The other element of surprise in the making of this cake was that I was baking at high altitude. Living in Colorado, first Boulder, then Aspen where it was very challenging, now Denver, has presented a fair share of complications due to higher pressure, thinner air and much, much drier air. Eventually, my grandmother sent me a copy of Pie in the Sky – and it has become my high altitude baking Bible. The author of the book breaks down recipes for varying levels of high altitude – each with a completely different recipe.

There is no “secret” to high altitude baking; at first I added more eggs to compensate for less moisture in the air, and it became too oily and eggy. I also fussed with the leavening agents (baking soda and baking powder) since they are also affected by the air pressure, and my cakes ended up crumbling or looking pathetic. Baking truly is chemistry, so I consulted the aforementioned book and my life has been much easier ever since.

Some basic tips I learned from the book are: decrease the amount of baking soda or baking powder by roughly 15%-20%, and for altitudes over 7,000 feet, decrease the leveners by 25% or more. The oven temperature is generally increased and the baking time is decreased, but I think that the bottom line is that there are really too many broad generalities when referring to “high altitude baking.” Yes, this term technically applies to levels of about 5,000 feet or more, but baking nearly twice that level in say, Breckenridge, which is well over 9,000 feet, is an entirely different animal. I hate to say there is no “magic secret” but there really isn’t – other than doing extensive research on the exact altitude you are living in or visiting.
Bake for 25 to 30 minutes in the preheated oven, until the cake springs back when pressed gently in the center. Cool in pans over a wire rack. When completely cooled, frost or fill as desired.

Buttercream Cake Ingredients

  • 1 cup white sugar
  • 1/3 cup butter, softened
  • 2 eggs
  • 1 1/2 cups all-purpose flour
  • 2 teaspoons baking powder
  • 1 pinch salt
  • 1 cup milk
  • 1 teaspoon vanilla extract
Preheat the oven to 350 degrees F (175 degrees C). Grease and flour two 8 or 9 inch round cake pans.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, mixing well after each addition. Combine the flour, baking powder and salt; stir into the batter alternately with the milk. Stir in vanilla. Distribute batter evenly between the prepared pans.
Bake for 25 to 30 minutes in the preheated oven, until the cake springs back when pressed gently in the center. Cool in pans over a wire rack. When completely cooled, frost or fill as desired