Mix uncooked beef, bread crumbs, oregano, salt and egg.
Press mixture evenly against bottom and side of ungreased 9 inch pie plate. Spread mushrooms, bell pepper, pepperoni and olives and then a thin layer of cheese on top of beef mixture. Repeat the layer without the cheese. This should fill up the pie.
Pour tomato sauce over toppings.
Bake uncovered for 25 minutes and the beef is no longer pink in center and the juice is clear.
Carefully drain the juices.
Sprinkle with cheese bake until the cheese is light brown.