If marshmallows get hard are they still good to eat?

If marshmallows have become hard, they are still safe to eat, but their texture and flavor may not be as pleasant. You can try reviving them by placing them in an airtight container with a slice of bread or a few Apple slices for a day or two to add moisture. However, if they show signs of mold or an off smell, it's best to discard them.