Pour 30ml of pastis into a Collins glass.
Add 10ml of orgeat syrup and stir gently to combine with the pastis.
Add ice cubes to the glass.
Pour 90ml of chilled water over the ice and stir briefly to integrate.
The louche - the milky cloudiness that appears when water hits pastis - is caused by anethole, the essential oil in anise, precipitating out of solution; always add water last to enjoy the full visual effect. Ice should go in before the water so the dilution is controlled and the louche develops gradually.
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