8 ounces fresh mushrooms, sliced (2-1/2 to 3 cups)
1-1/3 cups Chicken Broth
5-ounce can fat-free evaporated milk (2/3 cup)
1/4 cup all-purpose flour
1/4 cup sliced green onions
3 tablespoons grated Parmesan cheese
Dash of nutmeg
1/4 cup fresh bread crumbs (or 1/2 slice bread)
2 tablespoons finely snipped fresh parsley
1 teaspoon grated lemon zest
Lightly spray a 9-inch square baking pan with vegetable oil spray.
Steam broccoli spears until tender-crisp, then plunge into ice water to stop cooking. Drain and blot dry on paper towels. Arrange in baking pan.
Evenly place chicken over broccoli. Set aside.
For sauce, heat margarine in a medium nonstick skillet over medium heat. Swirl to coat bottom. Cook mushrooms, covered, for 7 to 9 minutes, or until they've been released of their juices. Increase heat to high and cook, uncovered, for 1 to 2 minutes to allow liquid to evaporate. Set aside.
Preheat oven to 375 degrees F.
Pour broth and milk into a medium saucepan. Whisk in flour. Bring to a boil over medium-high heat; cook until thickened, 3 to 4 minutes, stirring occasionally.
Stir in green onions, Parmesan, nutmeg, and mushrooms. Pour over chicken in baking pan.
In a small bowl, combine topping ingredients. Sprinkle over casserole. Bake for 25 minutes.