How to make
It is best to freeze the octopus before cooking it in the oven to make it softer.
Put the octopus in a large pot and put it on low heat, pour the lemon juice and cover it for 25 minutes. You can turn its head from the inside out. It will release all of the impurities. After the time has elapsed, remove it from the heat and leave it to cool.
Cut the potatoes into quarters and add the vinegar. The potatoes will immediately absorb some of the vinegar and will not fall apart during baking.
Now add the coarsely chopped onion, tomato, ground pepper, black olives, some capers, onion (cut into thin slices), black pepper and salt.
Add the bay leaf and pour the homemade olive oil over the oven-baked vegetables and if you don't have homemade, add extra virgin olive oil and add the white wine. Mix everything well and add the mushrooms.
Wash the octopus under a stream of cold water.
Arrange it on the mushrooms, then cover it up with aluminum foil and place it in the oven for 45 minutes at 390°F (200 degrees).
After the time has elapsed, take it out and stir, then place it back in at the same temperature for the next 20 minutes.
Now mix everything again and place the octopus with the oven-baked vegetables back into the oven for 20 minutes, but increase the oven temperature to 450°F (230 degrees).