3 leeks, light green and white part only, cleaned and finely chopped

1 pound brown (cremini) mushrooms, cleaned and sliced

1 tablespoon tomato paste

2 tablespoons all-purpose flour

1 teaspoon paprika

2 1/4 cups beef broth

1/3 cup creme fraiche or sour cream

2 teaspoons Dijon mustard

2 teaspoons lemon juice

2 tablespoons finely chopped parsley, for garnish

1. Heat 1 1/2 tablespoons of the oil in a large skillet on high heat. Dry the chicken off with paper towels and season with salt and pepper. Saute the chicken in batches, making sure not to crowd the pan, about 1 to 2 minutes on a side or until nicely browned on both sides and just cooked through. Remove to a side bowl and reserve. Repeat with another 1 1/2 tablespoons oil and the remaining chicken. Reserve.

2. Lower the heat to medium and add the remaining tablespoon of oil and the butter to the skillet. Saute the leeks until softened and lightly browned, about 5 minutes. Add the mushrooms and saute until nicely browned, about 5 more minutes. Season with salt and pepper.

3. Stir in the tomato paste and cook a minute or until lightly browned. Sprinkle over the flour and paprika and cook another minute. Add the broth, turn up the heat to high and scrape up the brown bits with a wooden spoon. Let boil a minute and then reduce the heat to medium. Add the cream, mustard and lemon juice, and cook another minute until nicely blended. Taste for seasoning. Return the chicken and any juices to the sauce and cook no more than 2 minutes or until just hot. Serve immediately over noodles and garnish with parsley.

(Diane Rossen Worthington is an authority on new American cooking. She is the author of 18 cookbooks, including "Seriously Simple Parties," and a James Beard Award-winning radio show host. You can contact her at www.seriouslysimple.com.)