1) Heat oven to 425 degrees.
2) In a 12-inch skillet cook beef, mushrooms, and onion over medium heat about 8 minutes or until beef is browned and onion is tender, stirring occasionally. Drain off fat. Stir in salt and pepper.
3) Meanwhile, grease a large baking sheet. Roll or pat dough to a 15x12 inch rectangle. Top dough with beef mixture, keeping filling within 1 1/2 inches of all edges. Fold edges over the filling , pleating as needed.
4) Bake tart 15 minutes or until crust is golden. Top with blue cheese, oregano (optional) and pizza seasoning (optional) Serves 4
5) Each serving 525 cal, 23g fat, 74 mg chol, 1041 mg sodium, 49 g carbs, 2 g fiber, 31 g protein.