Tsuboyaki (literally, cook in a vase) means two things: one is to smother food in a vase-shaped cooker, and another is to use a snail shell itself as a cooker and process the snail, but usually, the latter cuisine is a typical example.
壺焼きは、壺状の調理器の中で蒸し焼きにするもののほか、巻貝の貝殻をそのまま調理器として使う料理法をも意味するが、後者の料理法の代表的な事例。