I love this recipe because it takes a delicious layer cake filled with frosting and finished with bright sprinkles and puts it in a portable and easy-to-eat package. What could be better than a colorful rainbow cake on the go?
For the cake:1.
Combine the flour, baking powder and salt in a large bowl and whisk until they are really mixed together. You have to mix all the dry ingredients together first, so that there are no clumps in your batter, which will create white spots. Set aside.2.
In a separate bowl, use an electric mixer on medium speed to blend the butter and sugar together, until they become fluffy. Make sure to scrape the sides of the bowl with a spatula so it's all mixed in from the sides.3.
Add the eggs, one at a time, to the butter-sugar mixture, with the mixer on medium speed. Again, make sure to scrape the sides of the bowl.4.
Add the vanilla to the milk and set it aside.5.
Mix about one-third of your dry ingredients into the butter-sugar-egg mixture, then blend in half of the milk, always mixing on medium speed.6.
Mix in the second third of the dry ingredients, then the remaining milk mixture.7.
Stop the mixer for a few seconds and use a spatula to push down anything sticking to the sides of the bowl as you go, then mix in the last of the flour mixture. Make sure it's all mixed in from the sides and everything is smooth. (You don't want any lumps, but don't overmix it — stop the mixer as soon as the batter is smooth.)8.
Divide the batter evenly into six portions. They don't have to be exactly identical, but you want them to be close: You can use any small bowls that are all the same size: Just slowly pour the batter into each of the bowls a little at a time until they are all at the same height (about 1 cup of batter per bowl).9.
Color the batter individually in rainbow colors: We use purple, blue, green, yellow, orange, and pink for our six-layer cakes. Start with a tiny drop of food coloring, stir it in completely, then add more until it is your desired color.10.
Spray six 1/8 sheet pans (approx. 4½- by 6½-inches) with cooking spray, then pour the colored batter into the greased pans.11.
Bake the cakes for 4 minutes without opening the oven door. Then rotate each pan so the front faces the back. Bake for another 4 minutes, or until a toothpick comes out clean when you insert it into the middle of the cake. (Cakes are very sensitive. The less you open your oven, the better your cake will come out!)12.
Let the cakes cool in the pans for 5-10 minutes. (When they're warm, they're really fragile, and that's when they tend to break.) Then flip them over onto a baking sheet or cooling rack and let them cool completely before you frost them.
For the frosting:
Use an electric mixer on medium speed to blend the butter until it is smooth. Add the cream cheese and blend it together until there are no lumps. Then add the vanilla. Stop the mixer and use a spatula to push down anything sticking to the sides of the bowl, making sure it's all mixed in from the sides and everything is smooth.
Mix in the powdered sugar a little bit at a time on the lowest speed. Use the spatula to push down anything sticking to the sides of the bowl, making sure it's all mixed in from the sides and everything is smooth.
Cut 12 circles using the cookie cutter from each colored cake pan. Place one cake round into the bottom of the container. Squeeze a small dollop of frosting, then place your second cake round slightly pressing down. Repeat until all 6 cake-round layers are stacked into the container. Squeeze a tiny dollop of frosting on the center of the last cake round then dip the top of the frosting into the bowl of sprinkles. Repeat the steps with the remaining cake rounds.