Pre-chill a Collins glass in the freezer for at least 5 minutes.
Pour the light white rum, overproof white rum, absinthe, falernum liqueur, green crème de menthe, and fresh lime juice directly into the chilled glass.
Fill the glass two-thirds full with crushed ice.
Insert a swizzle stick or bar spoon and swizzle vigorously between your palms until the outside of the glass is well frosted.
Pack the glass to the top with additional crushed ice, forming a domed ice cap.
Dash 3 dashes of aromatic bitters directly over the ice cap.
Garnish with a lime wedge and a bouquet of fresh mint sprigs inserted into the ice.
Serve immediately with a straw.
The swizzling technique is critical here - a proper swizzle chills and dilutes simultaneously while aerating the drink, producing a texture and frost you simply cannot replicate by stirring. Use a traditional Quararibea turbinata swizzle stick if you can find one.
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