Heat the oil in a large saucepan and sauté the onion and garlic until soft and fragrant.
Add the tomatoes, tomato paste, carrot, white wine, sugar, oreganum and parsley. Season with salt and pepper and simmer for 40 minutes.
Cook the linguine in salted boiling water until al dente.
In the meantime, heat the fish stock with the crushed garlic in a large frying pan. Add the mussels. Cover with a lid and cook for 5 minutes.Remove from the heat and discard any unopened mussels.
Melt the butter in a frying pan and stir fry the prawns, fish fillets and calamari rings for 2 to 3 minutes or until cooked through.
Add the prawn mixture, mussels, mussel cooking liquid and linguine to the tomato sauce.
Add the chopped parsley and season lightly with salt and pepper.
Stir through and serve.Recipe reprinted with permission of PinkPolkaDotFood. To see more recipes, click here.