Place a saucepan with oil and sweat the onion in it. Add the peas (I let them thaw overnight, but don`t necessarily have to) and add the broth, although I find the poultry broth more aromatic than the vegetable broth.
Simmer everything for about 15 minutes. Puree the soup finely, if you like it very fine, you can also pass it through a sieve.
Add the cream and the dash of sherry. Freshly grate the salt, pepper and nutmeg over the top.
If you want the soup a little more exclusive, you can divide and add trout fillets or smoked salmon strips. With toasted baguette.