When rainbow cake was the IT cake few years ago, I wasn't attracted to it. Maybe I found it tedious (it really is) and having to use artificial food colors. Furthermore, the colors will not add any flavor to the vanilla sponge cake. I'm not one who's fond of using artificial food colors. I prefer the au natural.
Then why am I baking it now? Because I've found out that I can use fruits and vegetables purees to get the colors needed and I just have to bake one to see how the colors will turn out.
As you can see the photos posted here, the colors are not as bright and vibrant as the artificial colors. But I'm still happy with it. Hope you will be too.
The cake layers are all chiffon sponge cake. I can only make 5 layers using the fruits and vegetables that I can lay my hand on.
The easiest color is yellow - just plain vanilla sponge cake.
For the green color, I used the concentrated pandan juice. This is no sweat for me as I bake my famous pandan chiffon cake quite frequently. Pardon my self praise about pandan chiffon cake (my family and friends said so ..). You can also use spinach juice (I don't quite like the taste) or matcha (japanese green tea powder).
For the orange color, use carrot puree. The color did not turn out as vibrant as I've hoped to. Nevertheless, it still looked a little like pale orange or peach.
For the purple color, use blackberry or dark cherries juice. I used the canned fruit juice. You can blend or juice fresh blackberries too. I'm delighted with how the purple color turned out. It's great.
Use blueberries to get blue color. Unfortunately, it looks more like grey than blue. So disappointed.
Fresh cream is used in this cake between each layer and the top. Cream cheese or buttercream frosting can be used too. To make the cake look more attractive, I decorate it with lots of fruits. Healthy, isn't it? (Trying to cheat ourselves that eating cake is healthy .....) But, I would say it's quite healthy .... no butter being used as the cake layers are chiffon sponge cake. So go ahead to have more than one slice.