the cake that started it all. mmm.
strangely enough, i found this
recipe on a news site that i frequent. it was so visually stunning that i had to try it out - having never made a cake from scratch before, i didn't have high expectations, but - go big or go home i guess. :)
i went into this cake with none of the usual "baking hardware" - amazingly, i still don't own a hand mixer or food processor. i had at my disposal an immersion blender - which, while fantastic, is not conducive to fluffy buttercream icing. after i purée'd the hell out of it - i made the decision to toss in some flour for thickening purposes. it did well enough after that. and if you're keeping score, this would be attempt #1 at that dang icing. ready, fun!
Super Duper Rainbow Cakewhat you'll need:HARDWARE:
bowls, bowls, and more bowls. i have a set of mixing bowls and i used them all, washed, and reused about half of them.
3 (or more or less) 9" cake pans. i have 3 so i just washed them after round one and used them again. you'll be making 6 layers.
a whisk
a hand-mixer or stand-mixer or immersion blender (+flour)
spoons for transferring batter from bowl to bowl to pan
a spatula or 3
WHITE CAKE:
batch #1:
12 TBSP unsalted butter - softened
1 1/2 C sugar
2 C flour (all-purpose)
2 TSP baking powder
1/4 TSP salt
6 large egg whites
3/4 C milk
2 TSP vanilla extract
red, orange, & yellow food coloring
batch #2:
12 TBSP unsalted butter - softened
1 1/2 C sugar
2 C flour (all-purpose)
2 TSP baking powder
1/4 TSP salt
6 large egg whites
3/4 C milk
2 TSP vanilla extract
green, blue, & purple food coloring
LEMONY BUTTERCREAM:
to fill:
9 egg whites
1 3/4 C sugar
4 sticks of butter - room temp - cut into 1/2" cubes
2 TSP lemon extract
to frost:
5 egg whites
1 C sugar
2 sticks butter - room temp - cut into 1/2" cubes
1 TSP lemon extract
what to do:WHITE CAKE:
batch #1:
preheat the oven to 350.
in a large bowl, mix (w/ a whisk or hand-mixer on low) the butter and sugar for about 5 minutes, until it's light and fluffy.
in a separate bowl, stir together the flour, baking powder, and salt.
in another bowl, combine the egg whites, milk, and vanilla extract.
add 1/3 of the flour mixture to the butter/sugar bowl then 1/2 the milk mixture - thoroughly whisking or beating between each addition.
continue to add mixtures until everything is combined and has a gooey, batter consistency.
divide the batter evenly into 3 bowls and whisk a fair amount of red, orange, and yellow (respectively) food coloring into each bowl.
pour into the pans and bake for 15 minutes each.

when you remove them from the oven, let them rest for ten minutes in the pans.
then flip, cover, and stash them in the fridge while you work on batch #2.
batch #2:
same deal only green, blue, and purple food coloring this time.

LEMONY BUTTERCREAM:
**depending on how much of this icing to want to pack in between the layers, you may need to make this recipe twice. i made it once (only because i literally ran out of butter) and made it work by thinning out my fill layers. keep an eye on it as you fill and ration accordingly.**
to fill:
cook the egg whites and sugar in a small saucepan over medium heat, whisking constantly until the sugar is completely dissolved.
pour into yet another bowl and whip on high speed until room temp.
then, on a medium-slow speed (this is where the immersion blender starts to be less-than-ideal), add the butter piece-by-piece until it is completely incorporated.
turn the mixer back to high speed (welcome back useful immersion blender) and whip until it has come together, about five minutes.
add the lemon extract, beat briefly.
if it comes out for you like it came out for me (purée'd and runny) - i suggest tossing in a C of flour, mixing well with a whisk, and refrigerating for 30+ mins prior to assembly. if it came out wonderfully fluffy and thick, then more power to you and you can frost immediately. :)
to frost:
same deal, smaller portions.
ASSEMBLY:
stack purple layer.
add fill frosting.
stack blue layer.
add fill frosting.
stack green layer.
add fill frosting.
stack yellow layer.
add fill frosting.
stack orange layer.
add fill frosting.
stack red layer.
add fill frosting to cover the entire cake.
add frost frosting to cover the entire cake.
take a break - you deserve it.
