Cut half a lime into 4 wedges and place them in a sturdy Old Fashioned glass.
Add 10g (2 teaspoons) of white sugar directly over the lime wedges.
Muddle firmly to release the lime juice and express the oils from the skin - about 8–10 presses.
Fill the glass to the top with crushed ice.
Pour 60ml of white rum over the ice.
Stir briefly to integrate the rum with the muddled lime and sugar.
Top with a little more crushed ice if needed and serve with a short straw.
The Caipirissima is essentially a Cuban riff on Brazil's national Caipirinha - same build, same technique, white rum in place of cachaça. Muddle firmly enough to express the lime oils from the skin, but avoid over-muddling, which can introduce unwanted bitterness from the pith.
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