Rainbow cake!

When I first saw this cake on mojewypieki.blox.pl I just couldn't stop thinking about it. It was love at first sight :D I mean, just look at it! Isn't it awesome??? The recipe is probably already legendary - Whisk Kid herself baked her Rainbow Cake on The Martha Steward Show - but I'd like to share it with you anyway, since it's my first cake that I ever (EVER) baked! :) With one or two changes added by dorotus76, it goes like this:

Utensils:
- 2 or 3 medium/large bowls,
- kitchen mixer,
- kitchen scale,
- 6 small bowls for the batter,
- 6 cake pans (21cm/8in in diameter) [if you use smaller ones, you'll end up having a bit of a skyscraper cake. Trust me.]
- offset spatula.

Ingredients (for 6 layers):
- 226g butter,
- 220g sugar,
- 5 egg whites,
- 2 tsp vanilla extract,
- 375g flour,
- 4 tsp baking powder,
- 1/2 tsp salt,
- 355ml milk,
- gel food colouring (at least 3 colours: red, yellow and blue).

Cream frosting:
- 900ml double/heavy cream,
- 250g mascarpone (or cream cheese),
- couple of tbsps of powdered/icing sugar (I used 7 :D),
- vanilla or lemon extract.

All ingredients should be at room temperature.
In a bowl, whisk toghether the flour, baking powder, and salt.
In a separate bowl beat (with a mixer) the butter until light and fluffy.Gradually add the sugar, and then the egg whites, one at a time, beating well after each addition. With the mixer on low speed, alternately add the flour mixture and milk in a couple of additions, each time beating only until incorporated.

Weigh the batter and divide it evenly between 6 bowls.
(Time for some art ;)) Add the food colourings and mix them well with the batter. (Obviously, orange = red + yellow, green = yellow + blue, purple = blue + tiny amount of red).
A very small amount of the colouring should do the trick: I just dipped the 'thinner' end of a teaspoon :) Don't you worry that the colours seem to be a bit pale - they'll be brighter once baked.
Pour into the pans and bake about 15-20 min. in 190C/375F (until a toothpick inserted into the cake comes out clean).

(Time for the frosting ;)) Whip the cream until it holds stiff peaks. Then add the sugar, and vanilla extract and beat untill smooth. At the end, mix in the mascarpone.
Stack the layers of the cake in the rainbow order (beginning with the purple one, of course) and fill and frost. Don't forget about the sides of the cake.
Refrigerate the cake for about 3 hours before serving.
Voila :D

/)^3^(\