Bring the stock to the boil, then add the mussels and cook for 3-4 minutes until the mussels are open. Discard any mussels that do not open.
Strain the stock into a saucepan, reserving the mussels.
Pull the mussel shells in half, discarding the halves without the mussel meat, and keep to one side.
Place the pan with the stock back on the heat and reduce the temperature to a simmer.
Add the saffron, curry powder and cream, then bring it back to a simmer.
Add the fish, carrots, potatoes and leek and simmer for 2-3 minutes until tender.
Add the parsley and cooked mussels and stir through.
Season with salt and freshly ground black pepper.
Serve with the griddled bread.