This Cuban drink is one of the most popular cocktails in the world.
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Add lime juice to a collins or highball glass. Better choose the first: it is already and above, so soda will be exhausted more slowly.
To get a more intense citrus flavor, throw a slice of lime in a glass, shake it and remove the lime - you will take a little more flavor from the zest. Put ice cubes, pour in rum and cola. Mix well.