Rainbow Cake

This is the cake I demonstrated on BBC Radio 4’s Woman’s Hour in 2011. Not many people had heard of it then, but it’s now quite common. It’s still a marvellous cake tor both children’s and adults’ tea parties. Watch children’s faces (and adults’ too!) when you cut into the cake and reveal the rainbow slices.

Traditionally, to follow the colours of a rainbow, it would have seven layers: red, orange, yellow, green, blue, indigo and violet (though in the picture on the right I got carr