1. Preheat oven to 375.
2. In large skillet, cook ground beef and onion over medium heat for 8 to 10 minutes or until beef is thoroughly cooked, stirring frequently. Drain.
3. Stir in pasta sauce; cook until thoroughly heated.
4. Meanwhile, in medium bowl, combine shredded cheese and sour cream; mix well.
5. Separate dough into 8 triangles. Place dough in ungreased 9-inch glass pie plate in spoke pattern, with narrow tips overlapping rim of plate about 3 inches. Press dough in side and bottom to form crust;
6. Pour hot beef mixture into pie plate.
7. Spoon cheese mixture over beef mixture.
8. Bring tips of dough over filling to meet in center; do not overlap.
9. In small bowl, mix Parmesan cheese and butter. Spread evenly over dough.
10. Bake at 375° for 20 to 25 minutes or until deep, golden brown.