My marshmallows always stick together in a big clump. I keep them in a dry and cool place. This doesn't seem to work. Is there a way to store them so this won't happen?
Your best bet would be to place a desiccant into the container so that it absorbs the moisture which is causing your marshmallows to clump.
Silica gel packets would be fine and are often found in packets of jerky for this same reason. Alternatively some cornstarch would do since it absorbs moisture, but it may be harder to clean off of your marshmallows.