Preheat oven to 375F and grease a 9 x 13 pan
Put two layers of chicken into the pan and top with spinach, salt, and pepper. Top with mushrooms if desired
Whisk together olive oil, wine, and herb envelope. Pour over chicken
Lay a piece of foil over the pan, not tightly, and bake for 30 minutes
Remove from oven, remove foil, top with cheese, and bake for 5 minutes