taken from http://dairimama.blogspot.com/2011/07/rainbow-cake-by-dorie-greenspan.html
Adapted from Dorie Greenspan
2 1/4 cups cake flour
1 tablespoon baking powder
1/2 teaspoon salt (omit if u’re using salted butter)
1 1/4 cups milk or buttermilk
4 large egg whites
¾ cup sugar
2 teaspoons grated lemon zest
125gm unsalted butter, softened
1/2 teaspoon pure lemon extract
Gel or powder food coloring
2 tsp vanilla essence
1. Preheat the oven and put a rack in the middle or upper third of the oven. Butter two 5 inch pans and line with buttered parchment paper.
2. Sift together the flour, baking powder, and salt. In another bowl, whisk together the egg whites and buttermilk. I whisked the mixture using hand for about 1 minute.
3. Cream the butter and sugar in a mixer on medium speed for a full 3 minutes until very light and fluffy.
Beat in half of the egg-buttermilk mixture, then flour mixture, then the last of the egg-buttermilk mixture, and finally the last of the flour, beating until the batter is smooth. Beat the entire batter on medium high for two minutes until completely smooth and mixed.
4. Divide the batter in 6, dye each batter with different colour. Bake 20 minutes, rotating halfway through, or until a thin knife inserted in the middle comes out clean. Cool in the pans five minutes, then turn out onto a cooling rack. To ensure moistness, once the cakes are cooled, wrap immediately and chill.
For the Cream Cheese Frosting:
4 ounces butter, at room temperature
4 ounces cream cheese, at room temperature
4 ounces mascarpone cheese, at room temperature
1 cup powdered sugar
1 tablespoon vanilla extract
To make the frosting: Using the whisk attachment, whip the butter and cheese on high speed for about 5 minutes, scraping the bowl down as necessary. Reduce the speed to low and slowly add the powdered sugar until all is incorporated. Add the vanilla and mix to combine. Increase the speed to medium high and whip for a few minutes until the frosting is light and fluffy, scraping the bowl as necessary.
*Maisya tak guna mascarpone cheese, hanya cream cheese semata-mata.