For my Inside Out Independence Cupcakes, I made Martha’s white sheet cake. The idea here was to make really really white cake. How to get a cake white? Egg whites.
Start by turning on your oven, and buttering and flouring your sheet.
Take your three cups of cake flour. Sift it together with your salt and your baking powder.
Put the bowl aside.
In your mixer, or a separate bowl, take your butter and two cups of sugar and cream.
Then you’re going to add your flour mixture to your creamed sugar/butter, as well as your milk. Now, you must transfer your batter and put to the side. I know, I know, annoying, but the next step is MUCH easier with your mixer.
So now is the secret to making a white cake: egg whites. You don’t use any of the yolks, which can be seen as wasteful — but use your yolks for something else (perhaps a protein-heavy omelette?)
Take your eight egg whites, and your fourth cup of sugar, and beat on high speed until it forms stiff peaks (about 3 minutes).
TThey’ll look like this. Fold about a third into your cake mixture, and then add the rest, folding until just combined!
Here’s your delicious cake batter. You can add the vanilla at this point, which is when I did because I forgot. Whoops.
Pour your cake into your sheet, and bake in the oven until golden, about 35 minutes.
This is what it’ll look like when done.
Now you need some frosting. I made the frosting while my cake cooled, because my kitchen is one million degrees when the oven is on. I used one-half of the frosting recipe, because I didn’t need to frost the entire cake, and it worked out perfectly.
Take your butter, and cream.
Add your confectioner’s sugar. Add your salt and vanilla, then slowly add milk as needed to the consistency you want.
Split your frosting into two bowls, and let the fun begin!
I used food gel to make these colors. They’re great because you can control the amount you put in better than liquid, and it doesn’t make the frosting watery at all. And now, for the actual cake. Head over here to see what I did with my really white cake and color buttercream frosting!!