1. Heat two tablespoons margarine in a large frying pan over high heat. Sauté mushrooms for about 10 minutes, stirring frequently, until liquid is absorbed and mushrooms are beginning to brown.
2. Add garlic and parsley and sauté, stirring, for one more minute. Transfer to a bowl.
3. Pat chicken dry. Sprinkle with salt and pepper.
4. Heat olive oil and remaining margarine in the same pan. Dredge chicken in flour. Sauté for two to three minutes per side or until cooked through. When completely cooked, transfer to a serving dish.
5. Add shallots, rosemary, and thyme to the frying pan. Add the Marsala wine.
6. Bring to a boil while stirring and scraping up browned bits. Allow to boil until the liquid is reduced by half.
7. Stir in the beef broth. Simmer for two minutes.
8. Stir in reserved mushroom mixture and any accumulated chicken liquid. Simmer for another two minutes and pour over the chicken.