The original bicerin — espresso, hot chocolate, and milk-cream layered in a glass — was invented here in 1763 and the recipe has barely changed since. The cafe is tiny: half a dozen marble tables, a handful of chairs, walls hung with patrons' notes including Nietzsche's complaint about the price.
It is on the small piazza opposite the Santuario della Consolata, fifteen minutes' walk from Piazza Castello. There is always a queue in the morning. Worth the wait; the bicerin is genuinely better here than anywhere else in the city.