Press dough in bottom and up sides of a greased 9x13 pan. In a large skillet, cook sausage over medium heat until no longer pink, drain. Sprinkle over dough. Top with mozzarella.
In a skillet, saute mushrooms and onion in oil until onion is tender. Stir in tomatoes, oregano, salt, fennel seed & garlic powder. Spoon over mozzarella. Sprinkle with Parmesan cheese. Bake at 350 for 25-35 minutes or until crust is golden brown.