Preheat oven to 350°F. Prepare the broccoli and cheese sauce in the microwave according to package directions; set aside to cool slightly. Cook bacon, mushrooms, and green onions in a nonstick skillet over medium heat until bacon is cooked through and mushrooms are tender. Scatter bacon mixture in the bottom of the pie shell; place the pie shell on a baking sheet.
In a bowl, whisk together the eggs and milk, then stir in the broccoli and cheese sauce along with the Cheddar cheese. Pour the custard into the pie shell and bake for 35 to 45 minutes, or until center is just set and a knife blade comes out clean when inserted into the center of the quiche. Let cool for at least 10 minutes before cutting into wedges and serving.
280 calories; 16 g fat; 6 g saturated fat; 160 mg cholesterol; 11 g protein; 22 g carbohydrates; 2 g fiber;
510 mg sodium; 150 mg calcium (15% of daily value). Nutrition figures based on using fat free milk.