Clean and gut the fish, if the fishmonger has not already done so, taking care to remove the gills. Cut into 4cm (1½in) thick rounds and place in a large bowl. Add all the vegetables to the fish, together with the tomatoes, basil, spices and white wine. Cover and refrigerate overnight.
The next day, drain the ingredients, also saving the liquid. Heat a large frying pan with 100ml (3½ fl oz) of the olive oil and brown the pieces of fish over a high heat.
In a large saucepan, stew the vegetables from the marinade in the remaining 30ml (1 fl oz) olive oil for a few minutes. Add the browned pieces of fish and pour in the marinade, then add the rice and enough water to cover and simmer gently for an hour.
Reserve 130ml (4½ fl oz) of the broth for the rouille. Whether in a mouli, food processor or blender, break down the rest of the soup into the finest purée possible, then pass through a very fine sieve. Return to the cleaned pan and bring back to the boil, then adjust the seasoning and dilute with a little water (unless you have fish stock).
Meanwhile, for the rouille, strain the reserved broth into a small saucepan, add the saffron and then reduce to a mere 2 tablespoons. Blacken the chillies over an open flame, then place in a plastic bag for a few minutes before peeling and removing the seeds. Pound the chillies with the garlic and ½ teaspoon of sea salt using a mortar and pestle. Add the egg yolks and continue pounding to a smooth paste. Add the reduced broth, then slowly incorporate the oil to make a smooth paste. Check the seasoning and sharpen with a squeeze of lemon juice.
Serve piping hot with plenty of the rouille, some grated Gruyère cheese and some slices of baguette fried in olive oil and rubbed with garlic. Add a slug of Pastis, if you like.