With a potato peeler, remove a tongue of peel from an orange. Twist it over the glass to squeeze the essential oils into the cocktail. Garnish with the zest placed on the edge of the glass.
The sidecar appears for the first time in Robert Vermeire's book Cocktails: How to Mix Them, published in 1922. In that recipe, unlike the contemporary one, the drink contained all the ingredients in equal parts. However, its provenance remains uncertain: some believe it was created by Harry MacElhone at Harry's Bar in Paris, in 1921, for an eccentric army captain who went to the place with a sidecar. But there are also those who think it was born in New Orleans. Still, others hypothesise that it was created in London.
Certainly, the sidecar cocktail dates back to the golden age of mixology, according to the version of Frank Meier, the famous barman trained at the Hoffman House hotel in New York, who landed in 1921 at the legendary Hotel Ritz in Paris, where he remained on a permanent basis until 1943.