Champignon and hazelnut cream soup

It was the third of January when a friend of mine came to Lyon. I thought I would not meet her, as the stomach flu reached me just a few days earlier, yet we met and a few hours later ended up eating local ravioli, crunch chicken, and mushroom and hazelnut soup at a local brasserie. Although the soup was served a tiny bit colder than it should be, it was so good that I knew that someday I would recreate it at home. And I did. A simple and very French thing to serve any time of the year.

20 ml mild extra virgin olive oil
30 g celery stalks, chopped
80 g peeled onion, cut into pieces
5 garlic cloves, chopped
550 g champignons de Paris, cut into smaller pieces*
1 sprig of rosemary
1 tsp thyme leaves
1 l any stock you wish (except for fish stock)
80 g roasted hazelnuts
sea salt to taste
freshly ground pepper to taste
30 g butter or crème fraîche

serve
crème fraîche
chives or curly parsley

Heat a kettle and add oil, celery, onion, and garlic. Add salt and sauté for 10 minutes on a small heat. You want to soften them, not brown. Add champignons, rosemary, thyme, stock, and hazelnuts. Turn the heat on, let it boil and then turn the heat to medium-high. Boil for 25 minutes. Take off the heat and let it cool for a bit (5 minutes). Blend until smooth. While blending, add butter or crème fraîche, whichever you prefer to use. Pour back into the kettle, taste for salt and pepper, and heat till the first bubbles appear. Serve with some crème fraîche, maybe parsley, and definitely pepper.

* If you prefer a more distinguished taste, cook champignons in 30 ml of olive oil until they are golden.