Fondants, fudges, and caramels can be recooked if they are under- or overcooked or if the candy has sugared, as long as the candy has not been scorched.
In a heavy saucepan, combine 1 1/2 cups water and the cooked candy. Place over low heat and stir with a wooden spoon until the mixture is well-blended. Place a tight lid over the saucepan and increase the heat to medium and bring to a boil. Remove lid. If sugar crystals are present, wash down the sides of the pan with a wet pastry brush. Clip on a candy thermometer and cook to the proper temperature. Pour out and cool according to the original recipe. Add more flavoring since the old flavoring will have cooked out. The candy will have a darker color as the result of the increased carmelization of the sugar during the longer cooking time.
If candy is not cooked long enough, several things can be done. You can recook the candy using the instructions above. In some instances, mixing dry fondant with the soft candy can make it firm. Melted chocolate (real milk, semisweet, or compound coatings, etc.) can be mixed with candy before it cools. When chocolate hardens, the candy will become firm. The candy can be cooled to thicken and then dipped in chocolate. If the candy is so soft that it cannot be handled, line candy molds with chocolate, spoon candy into molds and cover with chocolate.
When candy is overcooked, it can easily be saved, as long as it is not scorched. Recook the candy using the instructions above.