Stir all the ingredients in a bain-marie until warmed through. (If no bain-marie or double-boiler is available, pour very warm water into a mixing tin, then in a smaller mixing tin, add all the ingredients and nestle the smaller tin inside the larger tin until ingredients are warm.).
Pour into a preheated mug and top with 3 oz boiling water.
Garnish with an orange peel.
*Ginger syrup: Roughly chop 8 oz washed, unpeeled ginger (each piece about the size of your pinkie-tip). Put in a blender and combine with equal parts sugar and boiling water. Blend on high until mixture is smooth, then fine-strain through a sieve.