How to Unmold Gelatin
Allow gelatin to set until completely firm, several hours or overnight. Before unmolding, dip knife in warm water and run knife around edge of gelatin to loosen. Dip mold in warm water, just to rim, for 15 seconds. Lift from water and gently pull gelatin from edge of mold with moist fingers. Place moistened serving plate on top of mold. Invert mold and plate and shake to loosen gelatin. Gently remove mold.
Garnish with additional marshmallows just before serving.