Fondant can be a tricky thing, even for experienced professionals. It takes time and practice to make it right and keep it fresh.
With that being said, the climate you live in plays a major role in how you should handle your fondant.
If humidity is an issue and your fondant is too sticky, fret not. Just knead in a little confectioner’s sugar or corn starch and it will be good to go. If your fondant is on the drier side, some vegetable shortening or glycerin will do the trick. For colder climates, you may find that your fondant is stiff and hard to work with. While fondant novices may be tempted to add water, don’t give in to the temptation. Water will leave pock marks on your fondant and ruin its smooth appearance. Instead, put it in the microwave for a few seconds to make it easier to handle. With all of these tips remember, less is more — don’t overwork it.
Now on to storage. If stored properly, fondant can last for several months. Your safest bet is to roll your leftovers into a ball, coat it with a thin layer of white vegetable shortening, cover it in your choice of plastic wrap or the Innoseal System, and place it in an airtight container at room temperature in a dry, dark place. Pantries are ideal, especially for colored fondant. If you leave your fondant in direct sunlight or near electric light, that pretty purple color you spent time perfecting will soon be a different shade.
In terms of storing your finished product, a major point of contention in the baking world is whether fondant can be refrigerated or not. Generally speaking, fondant cakes shouldn’t be refrigerated. Remember, water and fondant don’t mix. Putting your cake in the fridge exposes your fondant to moisture, which can leave those ugly pock marks and destroy the integrity of your cake. Some experienced bakers invest in humidity controlled fridges to keep their fondant as fresh as possible, but don’t feel like you have to invest in a new appliance. If you must put your fondant covered cake in the fridge, it is imperative to set your fridge’s temperature to the warmest possible setting and store your cake inside a cardboard box wrapped in plastic wrap or Innoseal. The cardboard will help absorb the moisture, while the plastic wrap and Innoseal will serve as an extra layer of protection.