Wash and clean broccoli, onion and potatoes. Melt the butter in a large saucepan and saute the broccoli, the onion and the potatoes for 7 - 10 minutes. Add the chicken broth, the wine, salt and pepper and let simmer for 20 minutes. Place the soup in a mixer and mash it. Put it back in the saucepan, add the mink and let it boil for 6 minutes. Serve hot with some cream on top and some pepper.