How to change what goes into a batch?

[JonnyLawless]

Love this game, but I've had some question about the interface. When building at the castle, the only rule that I'm aware of is that at least one of the cubes must be food. The games I've played so far there's only one option for donating. A recent turn said I could pay with food, stone and wood. I had extra food, and would have swapped one of those in, but I saw no way how to do that.

[Shivaware]

All of the cubes in a batch must be different.