Boil 120ml of water. Place the butter, sweetener, cinnamon, nutmeg, and allspice into an Irish coffee glass or mug. Use a spoon to mix well into a paste.
Step 2
Add in the vanilla extract, pour in the spiced rum, and give it a stir. Top with hot water and stir until the sweetener has dissolved and the butter has melted.
Step 3
Garnish with a cinnamon stick or star anise (optional). Serve and enjoy!