Heat the olive oil in a large skillet over medium-high heat. Add the ground beef, onion, garlic, Italian seasoning, salt, and black pepper. Cook and stir until the beef is browned and the onion is tender, about 10 minutes.
Stir in the tomato sauce and reduce heat to low. Simmer for 15 minutes.
Meanwhile, scoop out the seeds from the zucchini halves and discard. Place the zucchini halves in a 9x13-inch baking dish.
Spoon the beef mixture into the zucchini halves. Sprinkle with the mozzarella cheese.
Bake in the preheated oven until the cheese is melted and bubbly, about 15 minutes.
Interesting Facts
Zucchini is a type of summer squash that is high in vitamins A and C.
Ground beef is a great source of protein and iron.
Tomato sauce is a great way to add flavor to any dish.