Cafe Onion Seongsu

A 1970s metal factory turned into the industrial-chic cafe that defined Seongsu.

Order the pandoro, an Italian brioche piled with a snowdrift of powdered sugar, plus the salt bread (소금빵).
The original Onion location, set inside a former 1970s warehouse that was once a supermarket then a metal factory.
Bare grey walls, communal tables, a small garden.
Other Onion branches in Anguk, Mia, and Gwanggyo, but the Seongsu warehouse is the one that started the brand.