Heat the oil in a large saucepan, add the onion and garlic and cook over a medium heat for 5 minutes or until softened. Stir in the tomato purée and paprika, then pour over the wine and bubble for 1–2 minutes until reduced a little. Pour in the tomatoes and stock and bring to the boil.
Break the pasta into small lengths about 2.5 cm (1 inch) long. Reduce the heat so the mixture is simmering and stir the pasta into the pan. Cover with a lid and cook for 7 minutes, stirring occasionally to stop the pasta from sticking.
Add the mussels, cover and cook for 3 minutes until the mussels begin to open. Add the squid rings and prawns and cook for a further 2 minutes or until the seafood is cooked through and all the mussels have opened. Discard any mussels that remain closed.