Onyx Coffee Lab of Arkansas takes over Rosslyn's London Wall café for a weekend.
Onyx, named the World's Best Coffee Shop for 2026 and the first American winner, works the bar at 118 London Wall on 26 and 27 September. Its baristas serve a honey-cinnamon latte and an americano with English beer syrup alongside pastries from Hackney's Forno and Happy Endings soft serve.