Preheat oven to 350 degrees Fahrenheit. Spray a pizza baking pan (or baking sheet*) with nonstick spray.
Place lavash on baking sheet and begin assembling pizza. Spread marinara sauce over lavash, topping evenly with sweet potatoes, mushrooms, spinach and mozzarella cheese.
Bake for 5 to 7 minutes (or until outer edges are browned and crispy).
Remove from oven, top with parmesan cheese and serve.
Note: Let cool 5 minutes before slicing to prevent cheese from sliding off slices.