Heat oven to 350 degrees. In skillet,
cook bacon over medium heat 5-6 minutes, or until slightly rendered and beginning to curl. Remove bacon from pan and drain on paper towels until
cool enough to handle. Drain all but
1 tablespoon fat from pan and cook mushrooms over high heat 4-5 minutes, or until softened and any moisture in pan has evaporated, stirring occasionally. Add spinach leaves and cook 1 minute, or until just wilted. In bowl, lightly whisk eggs and stir in half and half, Parmesan, salt and pepper. Add mushrooms and spinach to egg mixture and stir to combine. Pour into pie crust and bake 20-25 minutes, or until eggs begin to set. Increase oven temperature to 400 degrees. Add bacon on top of pie. Bake 18-20 minutes, or until bacon begins to crisp and crust is golden brown. Let cool on wire rack 10-15 minutes before serving.