Ingredients

• 5 to 6 ounces (about 4 to 6) dried mushrooms such as Polish borowik or cepes
• 12 large dried shiitake mushrooms
• 3 quarts beef stock
• 5 medium ribs celery, chopped
• 2 large onions, chopped
• 5 carrots, chopped
• 1 pound white button mushrooms, sliced
• 1 cup orzo
• 2 tablespoons unsalted butter
• 2 tablespoons flour
• 2 tablespoons parsley, finely chopped
• 2 tablespoons dill, finely chopped
• 1 cup sour cream
• Salt and freshly ground black pepper

Instructions

1. Rinse the dried shiitake mushrooms. Place mushrooms in 2 cups of cold water, and soak for at least 4 hours or overnight, refrigerate. In a large pot, bring the stock to a simmer. Add the celery, onions, and carrots. Strain the dried mushrooms, reserving the soaking liquid. Add the strained soaking liquid to the soup. Chop the hydrated mushrooms into 1/4-inch pieces slightly larger than the diced vegetables, and add to the soup. Add the sliced white button mushrooms. Cover, and cook the soup until the vegetables are tender, about 1 hour. Bring the soup to a boil. Stirring constantly, add the orzo. Reduce the heat to a gentle boil, and, stirring occasionally to prevent the pasta from sticking, cook until the orzo is cooked through, another 6 to 8 minutes. Meanwhile melt the butter in a small saucepan over medium heat. Add the flour, and cook, stirring constantly until smooth, 3 to 5 minutes. Remove 1 cup of the broth from the soup, and add to the roux, whisking constantly until slightly thickened and free of lumps. Stir the thickened liquid into the soup. Add the chopped parsley and dill. Finish the soup with sour cream: Add 1/4 cup of the thickened soup to the sour cream. Whisk until smooth. Add the sour cream to the soup, whisking constantly until it is well incorporated, about 3 minutes. Season with salt and pepper, to taste.;