Peel the prawns whilst leaving the tales on. Cover and chill.
Place all the prawn trimmings and fish training into a pan and cover with about 450 mL of water. Bring to the boil, then cover and simmer for about 30 minutes.
Strain and reserve the stock
Heat the oil in a large saucepan and add the onion, leek, carrot and garlic. Fry gently for about 7 to 8 minutes, then stir in the turmeric.
Pour in the white wine, tomatoes and juice, reserve fish stock the herbs and orange peel.
Bring to the boil in cover and simmer gently for about 20 minutes
In the meantime prepare the Rourille sauce. Blend the bread in a food processor together with the garlic, chilli and tomato purée. Whilst the motor is still running pour in the oil in a steady thin drizzle until the mixture is smooth and thickened
Add the fish and seafood to the pan and simmer for 5 to 6 minutes or until the fish is opaque and the mussels open (discard any mussels that don't open)
Remove the bay leaf and orange peel
Seeds in the stew and serving bowls with a spoonful of the rouille sauce and sprinkle with the Parmesan and parsley