Cook meat in frying pan until completly browned. Drain. Cut zucchini down the middle long ways. Scoop out seeds and put in bowl along with meat, bread crumbs, garlic, half can of sauce, olives and parmesean. Mix well.
Stuff zucchini with mixture and place into a shallow baking pan and cover with foil.
Bake in preheated oven for 45 minutes. Take out of the oven and remove foil. Sprinkle mozzarella over zucchini and place broil until cheese is slightly browned. Let cool, serve.