The low-fat mushroom ragout can also be served over toast points or as a side dish.
Melt butter in heavy large Dutch oven over medium-high-heat. Add garlic and sauté 30 seconds. Add onion and sauté 2 minutes. Add mushrooms and sauté until tender and most liquid in pot evaporates, about 10 minutes. Reduce heat to medium. Add flour and stir 1 minute. Add white wine and cook until mixture thickens, stirring frequently, about 3 minutes. Mix in sour cream, then nutmeg. Season mushroom mixture to taste with salt and pepper. Add linguine to pot; toss to blend well and serve.