Recipe and more photos under the cut.
I made this cake for a party when I only had a few hours to spare. Surprisingly, considering that this is my first time trying out Rainbow cake, it turned it really well, and had the added benefit of being very easy to make.
250g flour (this was because it was a large pan (9″). You can adjust the quantity accordingly.)
50ml vegetable oil
6 tablespoons milk
1 teaspoon vanilla essence
2 teaspoons baking powder
1 teaspoon baking soda
Food colouring in the VIBGYOR shades
Gems/MnMs in the VIBGYOR shades
Royal icing ingredients (one egg white, 300g icing sugar, 2-3 tablespoons lemon juice, 1 tablespoon milk if required.)
You will also need toothpicks for stirring the colouring into the batter, and 7 bowls for each colour of batter.
Beat the butter with the eggs and sugar until they turn fluffy.
Sieve in flour, baking powder, and baking soda. Mix well.
Add the vegetable oil, milk, and essences.
Separate the batter into 7 equal quantities, to go into the 7 bowls.
Grease the baking mould with butter/oil.
Mix in the desired food colouring into each of the 7 bowls. Make sure that each colour is vibrant and distinct from the others because the batter runs together when baking and shades of colour too close together will end up mixing into one giant blob.
Now comes the fun part. You get to make rainbows!
You can start with either violet, or red, whichever colour you want to see on the outermost ring of your cake. Simply drop the batter into the absolute centre of the baking dish. It will spread, don’t worry about this. In fact, tap it on the counter to ensure that it spreads to all corners of your dish.
Now, drop the next colour of batter on top of this, again in the absolute center of the baking dish. For example, if you started with violet, as I did, now move on to indigo coloured batter. The violet batter should be a shallow pool at the bottom of the baking dish, drop the indigo right into the center of it. After a moment, you’ll see that the indigo batter is pushing the violet batter to the edges of the dish.
Repeat the process with the rest of the batter. The final result should look like this:
Bake the cake for 30-35 minutes at 200 degrees centigrade.
I topped my cake with Royal icing to bring to mind the clouds, and to really make the rainbow pop. I used Cadbury’s Gems (an equivalent to MnMs) to make the rainbow. I simply stuck them onto the icing while it was still wet, and after a while the icing dried to hold them in place.
The result was pretty spectacular, even if I do say so myself. The cake was eaten (and finished) almost as quickly as it was made!