Clean and prepare the seafood.
Heat the olive oil in a large heavy-based saucepan. Add the clams and white wine and steam until they open. Strain off the liquor to remove any sand and set the clams aside. Repeat, to open the mussels.
Wipe the pan clean and heat a little more oil. Quickly sear the prawns until they turn pink. Set aside while you repeat with the scampi and calamari. Finally, sear the fish fillets on both sides and set aside with the other seafood.
Add the tomato sauce to the pan and bring to the boil. Add the fresh tomatoes and chilli. Carefully return the seafood to the pan, starting with the fish, then the prawns, scampi, calamari, mussels and clams.
Add the strained liquor, avoiding any sand. If the dish is very thick you may need to add a little fish stock or water to thin slightly. Simmer for a few minutes until the flavours have melded.
Sprinkle with fresh parsley and serve with grilled bread that has been rubbed with a little garlic and good olive oil.