Preheat Oven to 400° F. Line a sheet pan with foil and set aside.

cut the zucchini in half lengthwise. Use a spoon to hollow out the centers of each half leaving about a 1/4 inch border all the way around. You can either discard the flesh that's been scooped out or chop it up and add it into the meat mixture. Place the prepared zucchini onto the sheet pan.

In a large skillet, heat a tablespoon of olive oil over medium-high heat. Add in the ground turkey and sauté crumbling it with a wooden spoon until it's browned and nearly cooked through.

Add in the diced onion and mushrooms (and reserved zucchini flesh if using) and sauté 2-3 minutes until they've softened. Add in the garlic, dried herbs, salt and pepper and sauté another minute.

Pour in the marinara sauce and balsamic vinegar then stir everything together. Reduce the heat to low and let it simmer for 10 minutes. Fill the zucchini boats evenly with the turkey filling and bake for 20 minutes. Remove from the oven and top with shredded mozzarella and bake for another 5 minutes. Remove from the oven and top with chopped fresh basil if desired.