Scrape the skin of the salt cod, then cut the fillets into roughly 4 cm (1.5-inch) square pieces, making sure to remove any remaining bones. Rinse thoroughly and pat completely dry with paper towels.
Dredge the fish pieces in flour, shaking off any excess, then fry them in plenty of hot olive oil until golden and cooked through. Transfer to paper towels to drain.
Char the skin of the bell peppers over an open flame or under a broiler, then peel off the charred skin. Core, seed, rinse, and cut the peppers into strips.
Pour approximately 100 g (about 7 tablespoons) of the used frying oil into a wide skillet or pan (adding fresh olive oil if needed) and gently sweat the sliced onions over low heat until soft.
Blanch, peel, seed, and dice the tomatoes, then add them to the onions. Season with salt and cook until the tomatoes have released and reduced their juices.
Add the pepper strips, a tablespoon of chopped fresh parsley, and the chili pepper to the skillet. Cook until the peppers have softened, then gently add the fried pieces of salt cod.
Cover with a lid and simmer over low heat for about 10 more minutes to allow the flavors to meld. Serve either warm or at room temperature.
