Boil the wine in a large pan. Add the mussels, cover and boil for about 2 minutes until the shells have opened. Transfer to a bowl, then remove them from their shells, discarding any that haven’t opened. Tip the juices through a fine sieve into a clean pan and add the stock, saffron and paprika. Bring to the boil, remove from the heat, cover and leave for 30 minutes. Stir in the cream.