Peel and finely chop the onion. Melt the butter in a saucepan, then gently sauté the onion and bay leaf until the mixture is soft. Stir in the sifted flour.

Add the cold chicken broth. Mix well and bring to a boil. Simmer over low heat.

Thinly slice the cleaned mushrooms and add them to the soup. Simmer over low heat for another 10 minutes.

Add the cream and heat for a few moments.

Season with black pepper to taste. Sprinkle with finely chopped chives.