1 ½ teaspoons butter
1 ¼ teaspoons olive oil
½ pound portobello mushrooms, chopped
¼ cup chopped onion
¼ cup chopped carrot
2 tablespoons chopped celery
2 tablespoons white wine
½ cup broth (chicken, beef or vegetarian)
1 ¼ teaspoons tomato paste
1 teaspoon butter
2 ounces enoki mushrooms
3 ½ tablespoons heavy cream
1 pinch ground nutmeg
salt, pepper to taste
8 ounces pasta (tagliatelle or fettuccine)
Melt 1 1/2 teaspoon of butter with olive oil in a large skillet over medium heat. Cook and stir the portobello mushrooms, onion, carrot, and celery until the vegetables are softened and beginning to brown, about 8 minutes. Transfer the mushroom mixture to a large saucepan.
Pour the white wine into the skillet and bring to a boil, dissolving any browned flavor bits from the bottom of the skillet. Allow the wine to cook for about 2 minutes, until reduced, and pour into the saucepan. Stir the beef broth and tomato paste into the mixture in the saucepan, bring to a boil over medium-high heat, then reduce heat to low. Simmer, partially covered, until the beef broth has reduced and the vegetables are very tender, about 35 minutes.
Melt 1 teaspoon of butter in the original skillet, and cook and stir the enoki mushrooms until lightly browned, 3 to 4 minutes. Remove the enoki, and chop. Stir the chopped enoki mushrooms into the sauce and simmer for about 10 minutes.
When the sauce is almost done, start cooking the pasta.
After simmering the sauce (as above), stir in the heavy cream just until heated through (do not allow it to reach a boil). Season with nutmeg, salt, and pepper to taste. Serve over the pasta.