1. Wash and quarter the mushrooms. Set aside a few mushrooms for garnish.
2. Remove the rind from the Brie and set aside a few slices.
3. Peel and chop the shallots.
4. Put all the ingredients in the blender. Season.
5. OR
Melt a knob of butter in a saucepan over medium heat. Add the shallots and mushrooms. Sauté for 1 to 2 minutes, stirring. Then add the broth, cover, and simmer for 15 minutes over low heat. At the end of cooking, add the Brie, cream, and pepper to taste. Blend everything until smooth. If needed, add a little water and blend again.
6. Adjust the seasoning and serve the soup by adding a few slices of Brie and mushrooms on top with a drizzle of cream.