Smoothing harshness

Alot of people have mentioned a smoothing liquid to help combat dryness of a mix.
The flavour is great, it’s a Blueberry Cheesecake mix.

What should I use, other flavours would alter the taste. Some have said a saline solution?

Any ideas on which one people?

2 posts were merged into an existing topic: Recipe advice

@Silhouette please merge with this

Recipe advice