Decorating a cake with rainbow icing involves applying different colored stripes of frosting and then smoothing them for a vibrant effect. Here's a simplified method based on the provided reference:
- Apply Rainbow Stripes: Pipe or spread different colored stripes of frosting around the cake.
- Smooth the Icing: Use a straight-edged cake comb to scrape around the cake, smoothing the frosting and blending the colors to create a rainbow effect. This will likely smear frosting everywhere, which is normal.
