You may have heard that to keep fresh-baked cookies soft without them drying up, you have to put a piece of white bread in the container with the cookies (via Mental Floss). This trick to keeping your brown sugar moist and soft works very much the same way.
According to Southern Living, simply take an apple (any type of apple will work in this situation) and cut it into slices. Southern Living’s tip suggests three slices of apple per every eight ounces of brown sugar, so you may need more apple slices depending on how much brown sugar you’re storing or softening. Place the apple slices into the container of brown sugar, making sure to prevent any air from coming in. After a few hours, the brown sugar will have begun to soften up.
Much like the white bread trick, MasterClass tells us, apple slices contain large amounts of moisture that can be redistributed back into the brown sugar, replacing the moisture that evaporated. While apple slices can lose moisture on their own over time, brown sugar collects the moisture. The apple slices may not be juicy and crisp by the time you take them out of the container, but your brown sugar will be back to its moist, crumbly texture.
If you’re more of a pottery fan than a produce fan, then you may be able to substitute apple slices for this other common material.