Preheat the oven to 400°F (200°C). Lightly coat a large baking dish with cooking spray.
Cooking spray
Slice each zucchini in half lengthwise and trim off the stems. Use a spoon to scoop out the center flesh, leaving about ¼ inch around the edges to form a shell.
4 medium zucchini
Place the zucchini halves in the baking dish and season with Italian seasoning, salt, and pepper. Bake for 10 minutes to soften slightly.
½ teaspoon dried Italian seasoning, Salt and pepper
Heat olive oil in a large skillet over medium-high heat. Add the ground beef and cook for 4–5 minutes, crumbling it as it browns.
2 teaspoons olive oil, 1 pound ground beef
Stir in the diced onion and cook for another 4 minutes, until softened. Add the garlic and sauté for 30 seconds. Season with salt and pepper. Pour in the marinara sauce, stir well, and let the mixture simmer for about 5 minutes to blend the flavors.
½ cup onion, 1 teaspoon garlic, 2 cups marinara sauce
Remove the zucchini from the oven. Spoon the beef and sauce mixture evenly into each zucchini boat. Sprinkle the tops with mozzarella cheese.
¾ cup shredded mozzarella cheese
Return to the oven and bake for 25 minutes, or until the zucchini is tender and the cheese is melted and lightly golden.
Sprinkle with fresh chopped parsley before serving. Enjoy warm!
Fresh parsley