Step 1

Place butter, brown sugar, vanilla extract, cinnamon, ginger, nutmeg, cardamom, clove, and salt for batter into a mixing bowl and cream together with a spatula until well combined.

Step 2

To make the drink, place about 2 tablespoons of the batter into a festive, heat-proof mug. Add 1 tablespoon cream, 3 tablespoons rum, and fill halfway up with some of the boiling water. Stir with a spoon until the batter dissolves and top off more water. Garnish with a pinch of nutmeg. Repeat until all 6 drinks are prepared and serve immediately.