Scrub the Norwegian mussels and check that all the shells are closed. Discard any that you are unsure of.
Steam the mussels in a dry saucepan covered with a lid on a high heat until they open, approx. 3-4 minutes. Discard the mussels that have not opened during steaming.
Take out the seafood and strain the stock. Add water if necessary so that there is enough stock for half a decilitre per portion.
Finely chop shallot and sauté in butter until shiny but not brown. Add the mussel stock and the saffron. 1 g saffron is approx. 1 tsp.
Pour in the cream and allow the sauce to simmer so that it thickens, or thicken with a little corn starch.
Season with salt and a little lemon.
Add the Norwegian mussels to the saffron sauce, and quickly heat through.
Serve with rice.