Start by bringing a large pot of salted water to a boil. Add the cheese tortellini and cook according to the package instructions until al dente. Once cooked, drain the tortellini and set aside.
In a large skillet, melt the Italian Herb Sauté Starter over medium heat. Add the diced onion and sauté until it becomes translucent, about 3-4 minutes. Then, add the diced zucchini and continue to sauté for another 5 minutes until the zucchini is tender.
Stir in the can of petite diced tomatoes (including the juice), and season with salt and pepper to taste. Let the mixture simmer for about 2-3 minutes, allowing the flavors to meld together.
Add the cooked tortellini to the skillet with the sautéed vegetables and toss gently to combine. Ensure that the tortellini is well-coated in the flavorful mixture.
Transfer the tortellini and vegetable mixture into a lightly greased baking dish. Sprinkle the grated mozzarella cheese evenly over the top, followed by the shaved Parmesan cheese.
Preheat your oven to 375°F (190°C). Bake the assembled dish for 20-25 minutes, or until the cheese is bubbly and golden brown on top.
Once baked, remove from the oven and let it cool for a few minutes. Garnish with fresh parsley, if desired, and serve warm.