Zanzibari fishers traditionally beat freshly caught octopus against shoreline rocks to tenderize it before it ever reaches the kitchen.
Fresh octopus is first tenderized by boiling, then simmered low in a ginger- and garlic-spiced coconut sauce with tomatoes until the sauce thickens and the octopus turns tender. It's a fixture of Zanzibari home cooking and seafood restaurants alike, usually ladled over rice or eaten with chapati.