In a saucepan, fry the finely chopped onion and leek in oil and add the chopped tomato pulp.
Gut the smaller fish and put them in the pot with the heads of the larger fish, a few mussels and shrimp croutons.
Add a pinch of saffron, pour over the fish stock and wine.
Meanwhile, clean the larger fish, cut into pieces and clean the cuttlefish (carefully, so as not to crack, remove the black dye sac and the translucent sharp ‘beak’), and remove the guts from the prawns and langoustines.
Remove the small cooked fish, heads and crunchies from the soup, discard the crunchies and remove the flesh from the fish.
Now put the pieces of larger fish into the soup pot and cook until tender. Baste with wine.
Then add the meat of the small fish, the remaining well-washed mussels (unopened!), the cuttlefish cut into rounds and the clean crustacean tails.
Cook until the mussels open, discard the closed ones.
Keep basting with wine while cooking. Apart from the saffron, do not add any spices or salt to the soup.