This is one of the very first recipes I learned from my mother-in-law in Bari: octopus cooked in its own water. And that's literally what it is. Get your hands on the best and freshest octopus you can (I use frozen when I can't get fresh). Pour about 4 tablespoons of olive oil into a pot, add the octopus, put the lid on, and cook over medium low heat till done. That's it. No water, no salt. As the octopus cooks it will give up its own 'water', which is why you want to serve this with a loaf of crusty bread. Cook time varies depending on the size: from 40 mins to an hour, until tender.