Gutted fish is cut into pieces with skin, bones and head. Briefly fry the onion slices in a suitable dish with olive oil, and caramelize it with some sugar. After a few minutes, add slices of garlic, chopped parsley, bay leaf, plenty of chopped tomatoes, sea salt and freshly ground pepper. Simmer for 6-7 minutes, pour white wine, and lay over pieces of fish. Boil for 10-15 minutes depending on the size of the fish.
Always cook stew in a wider dish, do not mixing it during cooking, just shake the pan occasionally.