ROASTED-VEGETABLE AND WINE SAUCE

Steps:

• Roast vegetables:
• Preheat oven to 450°F with rack in middle.
• Wash leek halves and pat dry.
• Toss leek, carrots, garlic, bell peppers, plum tomatoes, fennel, and onions with oil, then spread in a 17- by 14-inch roasting pan and roast, stirring occasionally, until well browned and tender, 1 1/4 to 1 1/2 hours.
• Soak porcini and make bouquet garni while vegetables roast:
• Pour boiling water over porcini in a bowl and soak until softened, 10 to 20 minutes.
• Meanwhile, wrap celery, parsley stems, thyme sprig, peppercorns, and bay leaves in a piece of cheesecloth and tie with string.
• Lift out porcini, squeezing excess liquid back into bowl, and rinse to remove any grit. Pour soaking liquid through a sieve lined with a dampened paper towel into another bowl.
• Make stock:
• Transfer roasted vegetables to a 6- to 8-quart pot and add wine to roasting pan, then deglaze pan by boiling, scraping up brown bits, 1 to 2 minutes. Add wine to vegetables in pot along with water (4 quarts), porcini and soaking liquid, bouquet garni, sun-dried tomatoes, and 2 teaspoons salt. Bring to a boil, then simmer, uncovered, until stock is reduced to about 6 cups, about 2 hours. Pour through a fine-mesh sieve into a large bowl, pressing firmly on and then discarding solids.
• Make sauce:
• Melt butter in a 3-quart heavy saucepan over medium heat and whisk in flour, then cook roux, whisking, 3 minutes. Add stock in a stream, whisking constantly to prevent lumps, then bring to a boil, whisking. Reduce heat and simmer, whisking occasionally, until slightly thickened, about 10 minutes. Season with salt and pepper.