1. In a large pot, melt butter over medium heat. Add mushrooms, garlic, green onions and salt; sauté until mushrooms have released their liquid and are browned, about 10 minutes. Sprinkle with flour and sauté for 2 minutes.

2. Gradually whisk in stock and wine. Add beans and bring to a boil, stirring often. Reduce heat and simmer for about 20 minutes to blend the flavors. Stir in cream, cayenne and salt and black pepper to taste; reheat over medium heat until steaming, stirring often.

3. Ladle into heated bowls and garnish with chives.