You have to clear them to open up the board and let more candies fall into play and the cover the jelly squares you need to clear as well.
The only way to get through the chunk of icing is to use special candies. You should really use whatever you can make, but the best combinations for this level are the wrapped + wrapped candy combinations, as well as the colour bomb + striped candy combinations.
You need to keep Odus balanced until moon struck is activated. If he falls off his scale, you will automatically lose the level. The good news about this is if you do activate moon struck, it will clear a candy colour off the board and most definitely help you clear the pesky blockers.