Chopping mushrooms: Cut mushrooms into 4 slices, then dice into 3 or 4 pieces.

Saute onion and garlic: Melt butter in a large pot over medium high heat. Add onion and garlic. Cook for 3 minutes until softened, but not golden.

Cook mushrooms: Add mushrooms and cook for 10 minutes, stirring regularly. Do not try to brown; they won't as the pot is too crowded but we do not need colour.

Simmer 15 min: Add vegetable stock, salt and pepper. Bring to a boil, then lower heat to medium and simmer gently for 15 minutes without a lid.

Cream: Stir in cream (or crème fraiche), then simmer for another 5 minutes.

Blitz: Transfer to a blender (do in batches, if necessary). Remove the cap from the feeding hole in the blender lid (Note 5), cover the hole with a folded tea towel. Blend until completely smooth.

Return to pot, simmer for a minute or two until bubbles caused by blending largely subside and soup is hot.

Serve: Ladle into bowls. Garnish with a drizzle of extra virgin olive oil or cream, croutons and parsley or (if you're feeling a bit fancy), chervil. Don't forget bread for dunking!