Heat the butter in a saucepan and heat the onion in it, then add the potato pieces and sauté briefly. Deglaze with wine and broth, put the lid on and simmer for 15 minutes. Puree the soup and refine with the cream.
Add the cleaned and sliced mushrooms. Simmer for another 5 minutes. Season with lemon juice and the spices and decorate with the chives.
Depending on the consistency, add a dash of water, broth or wine.