A recipe from Springwater Farm

Steps

1. Slice mushrooms ¼ inch thick. If mushrooms are big, cut into bite-sized pieces. Set aside.
2. To make stock, heat olive oil and 1 tablespoon butter in a large pot. Add onions, carrots, thyme sprig, 1 teaspoon salt, ½ teaspoon pepper adn cook over medium-low heat until vegetables are soft, about 10-15 minutes. Add 6 cups water, bring to a boil. Reduce heat and simmer uncovered for 30 minutes. Strain vegetables from liquid. Press excess liquid from vegetables. You should have about 4½ cups of stock. If not, add water to bring liquid up to 4½ cups and set aside.
3. While stock is simmering, heat remaining butter and add leeks. Cook over low heat for 15-20 minutes or until leeks begin to brown. Add sliced mushrooms, and cook for 10 more minutes, until browned and tender. Add flour and cook for 1 minute, stirring constantly. Add white wine and stir another minute, scraping the bottom of the pot while stirring.
4. Add stock, minced thyme leaves, 1½ teaspoons salt, 1 teaspoon pepper and bring to a boil. Reduce heat and simmer for 15 minutes. Add half and half, cream, parsley, salt and pepper to taste and heat through. Do not boil. Serve hot.