Fill a highball glass with ice.
Pour 30ml of spiced rum over the ice.
Top with approximately 120ml of ginger ale, pouring slowly down the side of the glass to preserve carbonation.
Stir gently once with a bar spoon to combine.
Serve immediately.
The vanilla and caramel notes in spiced rum are what sell the 'cream soda' illusion - brands like Captain Morgan or Sailor Jerry work especially well here. For a richer result, try a dark spiced rum like Kraken, which deepens the molasses undertone.
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