Preheat your oven to 375°F (190°C).
- Heat olive oil in a large skillet over medium heat. Add sliced zucchini and cook for 3-4 minutes, stirring occasionally, until softened but still firm. Season with salt and pepper, then remove from heat.
- In a separate bowl, mix the heavy cream, chicken broth, garlic powder, onion powder, and Italian seasoning. Add half of the mozzarella and all of the Parmesan cheese. Season with salt and pepper to taste.
- In a large casserole dish, layer sautéed zucchini on the bottom, then add the shredded chicken. Pour the sauce mixture over the top, and sprinkle with remaining mozzarella cheese.
- If desired, sprinkle breadcrumbs over the cheese for a crispy topping.
- Cover with aluminum foil and bake for 20-25 minutes, or until heated through and the cheese is melted. Remove foil and bake an additional 5 minutes if you added breadcrumbs for a crispy finish.
- Garnish with fresh parsley and serve immediately.