Another optional ingredient that is often incorporated into fudge and fondant formulations is premade fondant. Because fondant is a system containing very small sugar crystals, it acts as a seed when added to fudge, causing the fudge to crystallize more readily and with the minute crystals necessary for smooth texture. When using fondant to seed fudge, add it only after the fudge mixture has been cooked and has begun to cool on the marble. This timing ensures that the fondant crystals do not dissolve—which would defeat the purpose of using the premade fondant. A small percentage of fondant is sufficient to seed fudge and initiate crystallization.