Step 1: Place the leaf into a container and cover with cold water. Just cut the leaf into smaller if it does not fit as a whole. Step 2: Leave to soak for about five minutes until the gelatine expands and becomes pliable and wrinkly. Step 3: Remove the gelatine from the water and squeeze out any excess water. Step 4: Heat a liquid base for your recipe in a saucepan over medium-low heat. Stir in the gelatine leaf until dissolved, then pour the mixture into moulds to set. If your recipe does not call for a warm base, you can melt the gelatine on its own in the saucepan, then stir in your cold ingredients off the heat.