Put the salmon skin-side up In a wide shallow pan. Pour the wine over; then add the basil sprigs to the pan and sprinkle the fish with salt and pepper. Bring the wine to the boil, cover the pan and simmer gently for no more  than 5 minutes. Using a fish spatula, lift the fish out of the pan and set aside to cool a little. 

Add the tomatoes and cream to the liquid remaining in the pan and bring to the boil. Stir well, then lower the heat and simmer, uncovered, for 10-15 minutes. Meanwhile, cook the pasta according to the instructions on the packet. 

Flake the fish into large chunks, discarding the skin and any bones. Add the fish to the sauce with the prawns, shaking the pan until the fish and shellfish are well coated.Taste for seasoning. 

Drain the pasta and tip it into a warmed bowl. Pour the sauce over the pasta and toss to combine. Serve immediately, garnished with fresh basil leaves.