Chicken with Mustard Cream Marsala Sauce

4 skinless, boneless chicken breasts
Salt and freshly ground pepper
2 Tablespoons olive oil
2 Tablespoons butter, divided
1 medium onion, minced
1 pound fresh mushrooms, sliced
3 cloves garlic, minced
1 cup dry Marsala wine
8 ounces cream cheese
3 Tablespoons heavy whipping cream
2 Tablespoons Dijon mustard
2 Tablespoons chopped fresh parsley
12 ounces fettuccine, cooked according to package directions

Cut each chicken breast crosswise into 3 pieces. Sprinkle chicken with salt and pepper. Heat the oil in a heavy large skilled over high heat. Add the chicken, and cook just until brown, about 4 minutes per side. Transfer chicken to a plate and cool slightly.

While the chicken cools, melt 2 Tablespoons butter in the same skillet over medium-high heat. Add the onion and sauté until tender, about 2 minutes. Add the mushrooms and garlic; sauté until the mushrooms are tender and the juices evaporate, about 12 minutes. Add the Marsala and simmer until it is reduced by half, about 4 minutes. Add the cream cheese, whipping cream, and mustard. Stir until smooth. Cut the chicken breasts crosswise into ¼-inch-thick slices. Return the chicken and any accumulated juices to the skillet. Simmer, uncovered, over medium-low heat until the chicken is just cooked through, and the sauce thickens slightly, about 5 minutes. Stir in the chopped parsley. Season the sauce to taste with salt and pepper. Swirl the cooked fettuccine onto serving plates. Spoon the chicken mixture over top. Garnish with parsley sprigs and serve. Yield: 4 to 6 servings.