Fill an old-fashioned glass with ice cubes.
Pour 45ml dark rum over the ice.
Add 30ml Tia Maria.
Stir gently for 10–15 seconds to combine and lightly chill.
Serve immediately, unstrained, in the glass.
Tia Maria, being lighter and more coffee-forward than Kahlúa, is the preferred choice here - it lets the dark rum remain the dominant spirit rather than being overwhelmed by sweetness. If substituting, opt for a quality coffee liqueur with a similar dry, espresso-driven character.
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