This post comes straight from the inspiration of the internet. I am forever reading food and photography blogs looking for devine inspiration. The idea behind this rainbow colored cake is definitely the rage right now but what is incredibly inspirational is the brilliant idea from a fellow Canadian blogger Rosie from Sweetapolita. Not only is she a tremendous baker but her photography is stunning, crisp and inspirational. Rosie not only made the rainbow cake but took this cake to another level with covering the cake in fondant and then using it as a blank canvas for her adorable daughter to draw on the cake with edible markers. Now what could be more fun for a kid than to be handed some markers and told they can decorate their own cake? With 6 nephews and 4 nieces ranging in age from 7 to 2 years old this cake spoke to me like none other. Wow – was all I could think! What I adored about this cake is the idea of watching this cake come to life in the artistic doodles of the birthday child. I couldn’t stop thinking that this is a cake could be made year after year and provide a snapshot of that child’s time of life fully represented in cake. I am pretty sure I read and re-read this fantastic post at least 50 times that day. I was in awe!
The orginal recipe for the Rainbow cake comes from Kaitlin of Whisk Kid. This brilliant girl has her own blog and has been banging out recipes for a couple of years. She appeard on Martha Stewart to demonstrate the very recipe! Wow – this girl is going places. Check out her Blog Post
Rainbow Cake via Whisk Kid
White Cake (but not really)
2 sticks butter, room temp
2 1/3 c (466 g) sugar
5 egg whites, room temp
2 teaspoons vanilla
3 c (375 g) all-purpose flour
4 tsp baking powder
½ tsp salt
1 1/2 c (355 g) milk, warmed for 30 sec in microwave to bring to room temp
Red, orange, yellow, green, blue and purple GEL food coloring. Liquid will not be vibrant enough!
Preheat the oven to 350F degrees. Oil and line how ever many 9” cake pans you have (I have three and I just reused them).
Sift together the flour, baking powder and salt. Set aside.
Cream the sugar and butter, then add the egg whites (I cracked them all into one bowl) and add them a little at a time. Add the vanilla and mix until fully incorporated. Then, alternating between wet and dry, add the milk and flour mixture in two parts.
Divide the batter amongst 6 bowls (you can do it by weight). Weighing directions: weigh your mixing bowl before you begin adding ingredients and then subtract the weight of the bowl from the final measurement after the batter is completed. Divide that number by six and add that weight of batter to each bowl), and then whisk a fair amount of the appropriate food color into each bowl. Keep in mind that the color of the unbaked batter will be the color of the baked batter. Pour into the pans and bake for 15 minutes each.
When you remove them from the oven, let them rest on the cooling rack, in the pan, for ten minutes. Then flip, cover, and stash them in the fridge to cool quickly.
Lemony Swiss Meringue Buttercream
To fill and crumb coat: 9 egg whites 1 ¾ c (350 g) sugar 4 sticks (454 g) of butter, room temp 2 tsp lemon extract
To frost: 5 egg whites 1 c (200 g) sugar 2 sticks (227 g) butter, room temp 1 tsp lemon extract
Cook the egg whites and sugar in a small saucepan over medium heat, whisking constantly, until the sugar is completely dissolved (test by rubbing some between your fingers. If it’s completely smooth, it’s done). Pour into another bowl (a stand mixer is preferable) and whip on high speed until room temp. Then, on a medium-slow speed, add the butter, waiting until each piece is completely incorporated before adding the next. After all the butter has been added, turn the mixer back to high speed and whip until it has come together, about five minutes. Add the extract, beat briefly and then use.
If the buttercream seems soupy after all of the butter is added and does not come together after whipping, refrigerate for 5 to 7 minutes and continue whipping until it becomes fluffy and workable.
Assembly Stack the layers in your preferred order and fill and frost as you would any other cake.
Sweetapolita’s Notes & Doodle Cake How-To:
1. For tips & tricks on making Swiss Meringue Buttercream, both Kaitlin & I have posts about this, so lots of info!
2. You may find my previous post 50 Tips for Baking Better Cakes helpful with this cake (and hopefully others).
3. I was worried at first that I somehow made the layers too thin, but they were perfect, so don’t panic when they seem almost pancake-like! Once you pile 6 of those layers and all of that buttercream, the cake is a perfect height. Mine was about 4.5″ high. Use a 9-inch, 1/4″ thick cake board when building the cake.
4. To make the doodle cake, cover the buttercream cake in white fondant and refrigerate overnight. You will need approximately 2 lbs, 3 oz of fondant for a 9″ round 5″ high cake. Remove cake from refrigerator and let child (or anyone!) colour all over cake using AmeriColor Food Colour Markers. Place cake back in refrigerator every 15 minutes or so, if it begins to soften before child is finished (otherwise you will get dents in the cake). It’s also fun to have everyone at a birthday party sign the cake, write a message, draw a picture, etc!
5. You can store finished cake in refrigerator, but serve at room temperature or buttercream won’t be soft enough and the flavours won’t come through as intended. I typically take this type of fondant-covered cake out of refrigerator about 6 hours before serving. Just a note the cake will dent very easily when ready to serve, so avoid touching the cake itself.
*A note about the rainbow cake colours: I used AmeriColor electric gel colours to get such vibrant hues in the cake while adding minimal colouring. Here are the colours I used and links to find them:
Electric Purple, Electric Blue, Electric Green, Electric Yellow, Electric Orange, Super Red