Heat the oven to 350 F.
Grease a 9-inch tart plate.
Brown the meat and onion. Drain, add the sauce, salt, pepper, 1 tbsp of grated parmesan cheese, and oregano. Let it simmer while preparing the crust.
Separate the dough into 10 small rolls, place them at the bottom and on the edge of the plate to form a crust. Put the meat mixture in the plate. Arrange the mushrooms and tomato slices on the meat and cover with mozzarella cheese. Arrange the bell pepper rounds and olives on top of the cheese and sprinkle with the remaining parmesan cheese.
Bake in the oven for 20 to 25 minutes or until the crust is golden brown.