Ingredients
1 ounce dried porcini or other dried wild mushrooms
1/2 cup boiling chicken broth
1/4 cup dry madeira wine
1/2 cup butter (NO substitutes)
1/4 cup chopped onion
1 pound fresh button mushrooms, sliced (about 6 cups)
4 ounces shiitake mushrooms, sliced, stems removed (about 1 1/2 cups)
2/3 cup flour
8 cups chicken broth
1/2 teaspoons cracked black pepper
1 1/2 cups buttermilk
Preparation
Place dried mushrooms in a small bowl. Add the 1/2 cup broth and the wine. Let stand 30 minutes. Drain and discard the excess liquid. Coarsely chop mushrooms; set aside. Melt butter in large saucepan over medium heat. Add onion; cook and stir for 2 to 3 minutes still tender. Stir in fresh and dried mushrooms; cook 3 to 4 minute more or till most liquid has evaporated. Stir in flour. Add the 8 cups broth and pepper. Cook and stir to boiling. Reduce heat; cook and stir, uncovered, for 30 minutes more.
Remove 4 cups soup mixture; puree in blender or food processor. Return to saucepan. Stir in buttermilk and heat through. Do not boil. Make-ahead tip: prepare soup through pureeing step; cover and refrigerate up to 1 day. To serve, stir in buttermilk and heat through.
