Level 1823 - How to get yellow candies?

Laurie-4

When I AM unable to unlock some or all of the side candies, they don't turn into the required yellow candies when matched. I end up with the side bar full of random colored candies, and no yellows on the board. What am I doing wrong?

StuckInATree

Don't touch the mystery candies, they will all be revealed when you remove the cake bomb. They should all turn into yellow ones as you can see here: https://www.youtube.com/watch?v=z5mRCVWwedg