Its name literally means 'smashed cake' — eating it correctly means pressing down and cracking the crisp top sheet so it shatters over the soft, steamed layer underneath.
A soft, freshly steamed rice-paper sheet is pressed together with a dry, grilled rice cracker, then smacked flat so the brittle top layer shatters against the chewy one beneath, torn into pieces and dipped into mắm nêm, a pungent fermented anchovy sauce. It's often sold alongside hến (tiny river clams) at the same roadside stalls around Hội An and the wider Quảng Nam coast.