Fill a collins glass to the rim with ice.
Pour in the cold tonic water and let the foam settle.
Drop in a wide strip of orange peel.
Pull a fresh espresso and pour it slowly over the ice so it layers across the surface.
Serve unstirred and let whoever is drinking it mix the two on the first sip.
Popularised by third-wave roasters in southern Sweden in the early 2010s and now on café menus worldwide. Use a light, fruity single-origin; a dark Italian roast turns muddy against quinine. Pour the espresso last, and do not stir it in.
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