- 2 ounces dried cèpes , morels, or chanterelles
- 1/4 cup Madeira wine
- 8 Tbsp. (1 stick) unsalted butter
- 2 cups finely chopped yellow onions
- 2 pounds fresh mushrooms
- Salt and freshly ground black pepper , to taste
- 4 cups chicken stock
- 1 pint heavy cream (optional)
Melt the butter in a large heavy pot over low heat. Add the onions and cook, covered, over low heat until they are tender and lightly colored, stirring occasionally, about 15 minutes.
Trim the stems from the fresh mushrooms and save for another use. Wipe the caps with a damp cloth and slice thin. Add the caps to the soup pot, season with salt and pepper and cook over low heat, uncovered, stirring frequently, 15 minutes.
Carefully lift the mushrooms from the bowl with a slotted spoon and transfer to the soup pot. Let the wine settle a moment and then pour it carefully into the soup pot, leaving the sediment behind.
Add the chicken stock and bring to a boil. Reduce the heat, cover and simmer until the dried mushrooms are very tender, 45 minutes.
Strain the soup and transfer the solids to a food processor. Add 1 cup of the liquid and purée until very smooth.
Return the purée to the soup pot along with the remaining liquid and set over medium heat. Taste, correct the seasoning and thin the soup slightly with heavy cream if it seems too thick. Heat until steaming and serve immediately. Serves 6 to 8 portions