Remove the tough base and the stalks from the fennel.
Set aside the soft green fronds.
Slice the fennel bulbs into thin pieces and then into strips.
Put the fennel strips into a casserole with the white wine.
Cover and microwave onhigh for 14 minutes.
When the fennel is cooked, puree the mixture in a food processor.
Heat the sour cream (creme fraiche) onhigh for 1 minute.
Add to the puree with a pinch of salt, pepper and the grated nutmeg.
Puree once more.
If the mixture is not smooth enough, force it through a fine strainer (sieve), pressing it with the bowl of a spoon.
Pour the soup into 4 bowls.
Chop the green fennel fronds and sprinkle over.
If the fennel does not have enough green, substitute chopped fresh dill.
Slice the salmon into thin strips and arrange them decoratively on each portion.